System and method for protection of under-slab utilities from changes in soil volume

ABSTRACT

The present invention relates to a utility support framing system and method of use for structurally suspended concrete slabs of slab-on-voidform foundations. The inventive utility support framing system and method of use isolates utilities, hanger assemblies, and framing system components from soil so as to avoid problems created by volumetric soil changes which otherwise would damage utility lines under foundation systems. The inventive utility support framing system permits suspending utility pipes under a slab of a slab-on-voidform foundation while avoiding the problems of the prior art. The invention also relates to a novel mountable pipe clamp and method of use and a novel protective utility counterweight and method of use for transitioning a utility system from a suspended condition to a soil supported condition.

PRIORITY

This application claims priority to U.S. Provisional Patent ApplicationNos. 63/253,515, 63/245,835, 63/225,467 and 63/106,191.

TECHNICAL FIELD

The present application relates generally to an improved system andmethod for protecting plumbing lines, electrical lines and other utilitylines under a slab that is isolated from soils that exhibit volumetricchanges after construction, in which the under-slab utilities areisolated from these soils to protect them from the damage these soilscan cause, and in which flexible expansion joints in the utilities atthe perimeter of the slab allow the utilities to transition from anisolated condition under the slab to a soil-supported condition outsideof the slab, allowing utilities outside of a building to move due tochanges in soil volume without impairing the function or damaging theunder-slab portions of the utility lines.

BACKGROUND OF THE INVENTION

Problems due to expansive soils have been reported in many countries allaround the world. Every year they cause millions of dollars in repaircosts due to their severe damage to structures. Expansive soils oftencontain clay minerals such as bentonite, montmorillonite, and smectitethat have the potential to expand and shrink significantly due tochanges in moisture content. The expansive potential of the clay isgreater near the ground surface where the profile is subjected toseasonal and environmental changes in moisture content and has less soiloverburden pressure, from soil above, to counteract expansion.Increasing the moisture content of the clay often causes dramaticincreases in volume, especially near the ground surface where the groundsurface can rise up to 18 inches or more in some areas, with anestimated 6 inches of potential upward movement being common in manyurban areas where highly expansive soils are present. Similarly,decreasing the moisture content of the clay often causes dramaticdecreases in volume, especially near the ground surface where the groundelevation can drop in elevation as much as it is rises when the claygets wet. Fissures in the soil can develop during periods of time whenthe clay dries out due to seasonal variations in rain, growth of trees,or other sources. These fissures often allow water to penetrate todeeper layers when water is present. This often produces a cycle ofshrinkage and swelling that causes the soil to undergo progressivelygreater amounts of volumetric changes over time. This movement in thesoil often results in damage to buildings, especially in lightweightinfrastructure such as sidewalks, driveways, basement floors, pipelinesand shallow foundations that are not isolated from the volumetricchanges and do not have sufficient weight and/or stiffness to resist thechanges in stress caused by the volumetric changes in the soil.

The depth at which expansive soils can cause damage is also significant.As noted the 2014 Senior Thesis titled “An Examination of Changes withinthe Active Zone Moisture Content and Soil Swell Potential of ExpansiveClay Soils at a Site in Denton County, Texas” by Marc William Cappellwith Oklahoma State University, “Deep-seated swell is the additionalupward soil swell movement that could result from moisture changes andsoil swelling below a typical 10 foot (305 cm) deep active-zone (Farrowand Roland 2005).” As noted in a paper by Nelson, Overton and Durkee,all from Colorado, that was published for the Shallow Foundation andSoil Properties Committee Sessions at the 2001 American Society of CivilEngineers (ASCE) Civil Engineering Conference, titled “Depth of Wettingand the Active Zone,” “The term “active zone” generally refers to thezone of soil that either is contributing to or has the potential toproduce heave.” The 2001 paper describes how, for any specific soilprofile with expansive clay, there is a “Depth of Potential Heave” at“which the overburden vertical stress,” from the weight of the soilabove, “equals or exceeds the swelling pressure of the soil,” with the“swelling pressure” being the pressure required to prevent swelling. Asnoted in the Discussion and Conclusions of the 2001 paper, “There is nosound rationale behind assuming that the depth of wetting will stop atsome assumed depth. Instead, a more prudent assumption is to assumethat, in time, the depth of wetting will extend throughout the entiredepth of potential heave. This in fact, is realistic and conservative.”Therefore, for the purposes of this application, the term “active zone”will refer to the region of soil from the ground surface down to thedepth of potential heave.

There are other types of soil conditions which can cause changes involume similar to expansive soil. These other soil conditions caninclude without limitation: frost heave in colder climates where waterin the soil seasonally expands as it freezes and then contracts as itmelts; settlement in under-consolidated clay soil cases due to poorwater pressure dissipation over long periods of time after aconstruction project increases the overburden pressure such as by addingsoil to raise the ground elevation to a desired finish floor elevation;and, collapsible soils cases in which a small reduction in moisturecontent of some sand configurations with relatively low densities cancause an immediate and dramatic reduction in soil volume. While thefocus of this disclosure primarily discusses protection of under-slabutilities from expansive clay soils, the same comments often apply tothese other soil conditions which can be equally challenging in areas ofthe country where expansive clay soils are not present.

Most buildings require one or more utility lines to, for example,provide clean water and remove wastewater with a plumbing system.Utility lines buried in the ground and in contact with expansive soilare subject to stresses from expansive soil. Domestic water pipes areplumbing lines that provide clean water by a pressurized water line.Fire protection pipes are plumbing lines that provide water forautomatic fire sprinkler lines by a pressurized water line. Asignificant amount of water damage often occurs when pressurized waterlines break due to expansive soil damage. And, often the stresses fromexpansive soil are great enough to break these pipes. Expansive soil canpush plumbing lines up through the slab, damaging plumbing fixtures andeven causing damage to walls. When utilities transporting water in anyform leak, especially pressurized water lines, the leaks can causeexcessive saturation under a foundation. This saturation often leads tofurther soil expansion which often causes even greater damage to thefoundation and superstructure. Sanitary sewer pipes are plumbing linesthat transport wastewater away from plumbing fixtures such as toiletsand sinks by gravity, requiring that the lines slope downward to theexterior of the building with sufficient slope. When expansive soilmovement causes sanitary sewer lines to shift so that they no longerslope as intended, solids in wastewater often stop in the plumbing andthis causes sewage to build up and obstruct the plumbing, which becomesa health, safety and welfare problem for the occupants.

Several techniques have been used in the past to solve problems causedby the swelling and shrinking of expansive soils. Section 1808.6 of the2021 International Building Code (IBC) provides design requirements forfoundations on expansive soil using many older techniques in the priorart. These requirements do not address under-slab utilities but incertain cases they can reduce or even prevent damage to under-slabutilities from volumetric soil changes.

2021 IBC Section 1808.6.3 allows expansive soil to simply be “ . . .removed to a depth sufficient to ensure a constant moisture content inthe remaining soil,” which can protect under-slab utilities if all ofthe expansive soil is removed to expose dimensionally stable material,such as limestone, if dimensionally stable material happens to existnaturally near the ground surface. However, where such favorableconditions do not exist, the depth of excavation required would oftenexceed 10 feet below the ground surface. As noted above, there is nosound rationale behind assuming that the depth of wetting will stop atsome assumed depth, and the prudent approach is to assume the depth ofwetting can occur over the full depth of potential heave. Consequently,a disadvantage of the approach of removing the expansive soil to asufficient depth, and the reason this approach is often not selected bydesign professionals in many areas, is that the depth required tosufficiently address the problems associated with expansive soils is notpractical and/or more expensive than other options in the prior art. Anexample of this approach being impractical and/or expensive is whenconstructing an addition to an existing building and such an operationcould undermine the existing foundation. Another example of thisapproach being impractical and/or expensive is when constructing a newbuilding in a densely populated urban area where the property line is atnear the perimeter of the foundation so it does not allow a sufficientlydeep vertical retaining wall to be erected without permission of theadjacent property owner, which is often a municipality that uses theadjacent land for a road where they are not inclined to allow disturbingtheir property. Another disadvantage of this approach is that installingdimensionally stable material such as crushed limestone rock (oftencalled “flex base” and used for road construction) is often moreexpensive to purchase in areas where expansive clay soils arepredominant than other types of fill that cost less but are not asdimensionally stable, such as “select fill” consisting of soil with lessexpansive properties than the original soil in the ground. If selectfill is used in relatively shallow depths, such as a few feet, manygeotechnical engineers have found the level of damage to structuresassociated with the use of the less-desirable material to be tolerated;however, when depths greater than 10 feet are required, manygeotechnical engineers have concerns with the cumulative effect of thevolumetric changes that can occur in even select fill such as expansivesoil swelling and shrinking as well as settlement. Even when rock isencountered, many areas of the county have naturally occurring layers ofexpansive soil and rock layers alternating, sometimes with highvariability over a single building footprint. The intermittent layers ofrock can make excavation of the expansive soils to a sufficient depthhighly problematic, especially where there are large rock boulders thatcan be greater than the size of a school bus and much harder thanconcrete, causing unpredictably long delays in construction when theyare encountered. In cases where the slab is placed on the ground afterremoving expansive soil to a sufficient depth and replacing it withdimensionally-stable material, under-slab plumbing is typically buriedin the dimensionally-stable material. However, all of the challengesnoted above in removing and replacing expansive soil under slabs are thesame challenges in removing and replacing expansive soil under theutilities under those slabs. Therefore, in areas where expansive soilexists without a layer of competent bedrock that is encountered within afew feet of the ground surface and that extends well below 10 feet underthe ground surface, the approach of simply removing expansive soil toprotect under-slab plumbing is often not possible, not effective, notpractical, time-consuming, and/or more expensive than other options inthe prior art.

2021 IBC Section 1808.6.3 also allows expansive soil to be “ . . .stabilized by chemical, dewatering, presaturation or equivalenttechniques.”

Presaturation is still commonly used today in many areas, with thetheory that pre-swelling the soil will reduce or eliminate the potentialheave. This theory is based on an assumption, though, that the moisturewill not leave the clay subgrade and cause damage from soil shrinkage;however, this assumption has proven to be false in many cases where longperiods of drought and/or tree roots dry out the subgrade underbuildings and cause damage to foundations and under-slab utilities.

Dewatering is the opposite of presaturation and is a less commonapproach to reduce the potential vertical movement of expansive soilbecause, while in theory this may reduce the shrinkage, many peoplerecognize that if water is introduced to dewatered soil, the soil willswell.

In laboratories, companies that claim to be able to stabilize expansivesoil with proprietary techniques often produce laboratory evidence thatthey can reduce the volumetric changes of soil. These manufacturers donot typically claim to reduce all of the potential volumetric changes ofthe soil, but rather claim to be able to reduce it to a level where theybelieve the level of damage to a facility is tolerable. A paper by Petryand Little in the November/December 2002 edition of the Journal ofMaterials in Civil Engineering, titled “Review of Stabilization of Claysand Expansive Soils in Pavements and Lightly Loaded Structures—History,Practice, and Future” addresses some of the challenges withstabilization techniques and states, “It is always important and willcontinue to be important to clearly identify the mechanisms ofmodification and stabilization of clay soils. Only when these have beenclearly identified can we address problematic reactions and improve theproduct.” The paper further states, “Although some nontraditionalstabilizers are attractive alternatives, some of their producers areoverly aggressive in promoting their product. Some of these promotionsattack traditional stabilizers in an attempt to discredit them andobtain market share. These attacks often demonstrate a poor level ofunderstanding of the mechanisms involved.” And, the paper in summarystates, “The paper warns that competent engineers who apply theirprofessional knowledge judiciously must judge the effectiveness andappropriateness of all stabilizers. This knowledge is not cheap but mustbe gained through a dedicated effort to learn the fundamental conceptsof stabilization and to keep abreast of the state of knowledge as itdevelops nationally and in a given region. This requires dedication tocontinuing education and a proactive mindset in attitude by theengineer.” These comments speak to the difficulty in selecting aproprietary stabilization technique and knowing with confidence that itwill be successful. And, again, while some claim to come very close, itis important to remember that these techniques do not completelyeliminate any possible soil volume change. An added concern withchemical stabilization techniques can be concerns regarding potentiallyhazardous chemicals being introduced into the ground.

The prior art also teaches the controlling the moisture content ofexpansive soil under a foundation. For example, U.S. Pat. No. 4,534,143,issued to Goines et al., discloses a subsurface irrigation systemcausing water to slowly percolate into the expansive soil supporting afoundation so as to maintain the moisture content of the soil. However,it is virtually impossible for any artificial means of moisture controlto maintain absolutely constant moisture contents under a real facilityexposed to the highly variable conditions which are common. Moisturemigration n partially saturated soil is extremely complex and themechanisms are only generally understood by limited empirical evidencethat supports widely varying theories. What little evidence there isrelative to the complexity of the phenomenon actually indicates thatmoisture migration can occur even if there was a vertical barrier to anymoisture migration in or out under the perimeter edge of a foundation,making any attempt at complete moisture control potentially ineffective,with any interior moisture migration as soil conditions reach anequilibrium over time causing volumetric changes considering that inalmost all cases on real project there are non-homogenous soilconditions under a building, especially so as the moisture content ofsoil itself is a common non-homogenous soil condition. U.S. Pat. No.4,015,432, issued to Ball, discloses a foundation structure supported onexpansive soil moistened to its plastic limit. Through a moisturecontrolling barrier placed around the foundation periphery, moisture canbe added in an attempt to ensure that the moisture content of the soilremains at its plastic limit. However, a moisture controlling barriercannot be reliably effective in all cases as described above.Furthermore, it is only effective even in theory if it is deep enough,and the depth required in some instances, as discussed above consideringthe depth of the active zone, can be more expensive to construct thanother approaches which are more likely to be successful that do notrequire such a deep excavation.

2021 IBC Section 1806.6.2 allows foundations to be designed as aslab-on-ground foundation, where the entire bottom surface of thefoundation, including the slab, is generally supported vertically by thesoil. In general, when this approach is taken, any significant concernswith the potential magnitude of damage from volumetric changes inexpansive soil are typically addressed in part by attempting to lessenthe anticipated level of damage by applying the techniques describedabove as referenced in 2021 IBC Sections 1808.6.3 and 1808.6.4, and thechallenges with those approaches are discussed above. In addition, aprimary challenge with installing a slab-on-ground foundation overexpansive soils that are not completely removed or completely stabilizedis that some level of damage due to expansive soil should be expected.2021 IBC Section 1806.6.2 refers to design methods that attempt toaccount for soil-structure interaction, the deformed shape of the soilsupport as well as center lift and edge lift conditions, all of whichnote how a foundation will distort in three-dimensional geometry and anattempt is made to limit the distortion to an acceptable level. This isa common approach, especially for residences and small commercialstructures built in geographic areas where expansive soils areprevalent, however, damage occurs to both the superstructure and oftenthe under-slab utilities regularly in these types of facilities.Evidence of this is the large number of foundation repair companies thatare prevalent in geographic areas where expansive soils are common. Ifdamage occurs to an under-slab utility, the slab can be sawcut andremoved immediately above the area of broken utility so that the utilitycan be repaired and the slab repaired; however, damage to under-slabutilities can and often does occur, requiring expensive repairs.

2021 IBC Section 1808.6.1 provides an alternate to a slab-on-groundfoundation by permitting foundations be designed to resist differentialvolume changes and prevent structural damage to the supported structure.With this alternative approach, “Foundations penetrating expansive soilsshall be designed to resist forces exerted on the foundation due to soilvolume changes or shall be isolated from the expansive soil.”

An older method in the prior art that meets the requirements of 2021 IBCSection 1808.6.1 is to install an elevated foundation with a traditionalcrawlspace under the floor. When a properly designed crawlspacefoundation resists expansive soil forces, the superstructure beingelevated by a crawlspace protects the superstructure from expansive soildamage if the height of the crawlspace is greater than the magnitude ofthe potential vertical upward movement due to volumetric changes ofexpansive soils. There are two primary plumbing codes used in the UnitedStates today: the International Plumbing Code and the Uniform PlumbingCode. Neither of the latest published versions of either code explicitlyrequire isolation of plumbing from expansive soils. And, whereunder-slab utilities are supported by and buried in an expansive soilmaterial, volumetric soil changes can cause damage to the under-slabutilities, especially where the floor structure is isolated and thedifferential movement is greater than if the slab was a slab on gradefoundation. If under-slab utilities are hung from an elevated floorstructure after the elevated floor structure is installed, theunder-slab utilities being elevated above an under-utility spaceprotects the under-slab utility from expansive soil damage if theunder-utility space is greater than the magnitude of the potentialvertical upward movement due to volumetric changes of expansive soils.And, this post-slab isolation approach is actually common in portions ofcrawlspace foundations where access is provided to the under-floor spaceafter the floor structure is installed by means of an access opening,but this post-slab isolation approach is not typically applied to areasunder a slab where the depth of under-slab utilities is deeper than thesubgrade of a crawlspace. Many building codes require that underfloorspaces with access openings be considered crawlspaces and be ventilatedfor the safety of those that enter an under-floor space, either with anunpowered natural ventilation system comprised of sufficiently largeopenings in appropriate locations or with a mechanical ventilationsystem. However, a disadvantage of the natural ventilation system isthat animals such as snakes, opossums, cats, rats, mice, spiders,termites, bees, . . . etc. can often find access to the under-floorspace and create safety hazards for the occupants when they leave thebuilding and an ongoing nuisance for maintenance staff to address thesesafety hazards. Furthermore, water and/or humidity can often enterthrough natural ventilation openings and the prescriptively designednatural ventilation openings are sometimes not sufficient to be capableof removing the water and/or humidity, which can create problems withcorrosion of structural members, as well as potentially smells and/orfungal growth that can find its way through openings in the slab andcreate health, safety and welfare concerns. Mechanically ventilatedsystems are problematic for owners because they can have mechanicalfailures over time due to wear and tear on moving parts and exposure tothe elements, and it is common for occupants and maintenance staff tonot realize when these mechanical failures have occurred becauseoccupants generally do not go into under-floor spaces unless there is anevent creating a special need such as a maintenance activity. Whenmechanical ventilation systems stop functioning and there is not anatural ventilation system in place, the problems with moistureaccumulation can occur such as corrosion to structural elements thatcauses safety concerns and mold and smells that enter the occupied spaceabove the floor structure, which can all be dramatic where steel floorstructures are used that are not sufficiently protected from corrosion,such as with ungalvanized steel, and when openings such as floor hatchesdo not have robust and properly functioning seals.

A more recent alternative to a crawlspace type of foundation is theslab-on-voidform foundation type. An advantage of the slab-on-voidformsystem is that it can cost significantly less to construct than acrawlspace foundation. One reason a slab-on-voidform foundation can costsignificantly less is because the floor structure does not requireexpensive formwork, often regularly spaced unshored steel beams, to spanlong distances and hold up fresh concrete that has no compressivestrength while not deflecting an unacceptable amount. Another reason aslab-on-voidform foundation can cost significantly less is because theheight of the under-floor space of a slab-on-voidform foundation needsonly to be enough to accommodate the potential vertical movement ofexpansive soil whereas the height of the under-floor space of acrawlspace foundation must be adequate to meet building coderequirements for access and allow workers to do work such as removingany temporary shoring, installing any under-slab utilities that will beinstalled after a floor structure is in place, as well as inspectingconditions after occupancy and eventually doing repairs; and, the costof a foundation increases as the height of the gradebeams aroundperimeter increase due to increases in the height of an under-floorspace. And, another reason why the slab-on-voidform system can cost lessto construct is that a slab-on-voidform system typically does not havean under-slab drainage system since the under-floor space is notaccessible whereas crawlspace foundations typically have a drainagesystem. And, another reason why the slab-on-voidform system can costless to construct is that a slab-on-voidform system typically does nothave any lighting like is common in many crawlspaces because theunder-floor space of a slab-on-voidform foundation is not an accessiblespace. Another reason why the slab-on-voidform system is preferred overa crawlspace system is that a slab-on-voidform foundation can beinstalled at the ground level surrounding a building without requiringstairs to raise a floor elevation so as to provide natural ventilationof a crawlspace, if such a system is used. Another reason why theslab-on-voidform system is preferred over a crawlspace is that there isnot natural ventilation or mechanical ventilation as described above forcrawlspace foundations, and consequently no challenges associated withthose systems as described above, as there are with crawlspacefoundations. While the slab-on-voidform foundation type is a more recentapplication than a crawlspace foundation type, slabs with various typesof voids that could possibly be considered slab-on-voidform foundationshave been installed for over a century. With time, the slab-on-voidformfoundation type has evolved and a common manifestation is where drilledpiers and grade beams are installed that resist the forces of expansivesoil, then a layer of degradable carton voidforms are installed over asubgrade and the voidform system often includes a layer of Masonite atthe top, then a vapor barrier such as a plastic sheet is installed overthe voidforms, and then slab reinforcement is installed, and thenconcrete is poured to create the slab of a slab-on-voidform foundationin which the degradable carton voidforms deteriorate sufficiently thatthe slab is isolated from the expansive soil beneath the under-floorspace. One manufacturer of carton voidforms has indicated that theydistribute approximately 30 Million square feet of carton voidforms forthis type of application every year for new construction in NorthAmerica. Because there is no means of access to the under-floor space aswith a crawlspace foundation, under-slab utilities have historicallybeen supported by and buried in expansive soil when a slab-on-voidformsystem is used, which can cause damage like has been described above inexpansive soil conditions. It is true that moisture can accumulate in anunder-floor space of a slab-on-voidform system; however, today manyslabs are installed over vapor barriers with tape that adhere to theconcrete at the edges of vapor barrier sheets and penetrations toprevent moisture from rising above the vapor barrier in modernslab-on-voidform foundations. Studies have shown that, if there is not avapor barrier under carton voidforms, a subgrade typically has enoughmoisture with the moisture associated with fresh concrete as it cures,to cause modern carton voidforms to degrade in an acceptably fast time,several months for example, to lose enough strength that they will crushbefore telegraphing any loads up from a heaving subgrade, as they aretypically not wax impregnated today as in some decades past. A paper byDavid K. Isbell, P E titled, Performance of Cardboard Carton Forms aspresented on Feb. 21, 2001 to the Foundation Performance Association,and previously a part of a conference of the Texas Section of theAmerican Society of Civil Engineers (ASCE) states, “The moisture fromthe subgrade plus the hydration of the concrete appear to provideadequate deterioration of the boxes.” In some climates more than inothers, degradable voidforms can be problematic if it rains toofrequently or is too humid, because the degradable voidforms can losetheir strength before concrete is poured and there have been manycollapses of degradable voidforms when contractors have tried to takethe risk rather than remove all of the reinforcement and voidforms andstart all over again. Primarily for this reason, non-degradable voidformmaterials used in slab-on-voidform foundations are also in the priorart. In general, with voidforms that have non-degradable components,designers typically specify that they be installed in a manner so thatthey are capable of crushing under some theory of a crushing mechanismor that they are capable of cutting into a heaving soil under sometheory in which the soil will swell in between the non-degradablecomponents of a voidform system.

As an example of one of the more common systems of carton voidforms usedtoday in many parts of the United States to provide temporary supportfor a slab of a slab-on-voidform foundation, VoidForm® Products, LLCprovides a SureVoid® product corrugated paper voidform system withregularly spaced vertical cardboard partitions in a grid pattern with ahorizontal layer of cardboard across the top and bottom. Typically, alayer of Masonite is placed over the carton boxes.

As another example of systems in the prior art for supporting slabs ofslab-on-voidform foundations, Reliable Void Forms, of Austin, Tex.,provides an alternative to the traditional carton void form system.Instead of corrugated paper, Reliable Void Forms uses a molded pulp formmade of 100% recycled paper with a consistency and shape similar to anegg carton. Forms are produced in 61 cm×61 cm (24″×24″) squares withthicknesses of either 15 cm (6 in) or 20 cm (8 in). During installation,the forms can be cut, trimmed, or grinded to the appropriate shape andsize. Unlike cardboard forms, the manufacturer claims these forms can beused in wet or dry conditions. Also, due to their shape and weight, theycan easily be shipped, stored, hauled, and manipulated in the field.Once laid out on the site, the concrete is poured over the top.Gradually, over time, the forms will degrade, but until that happens,one theory purports that any soil expansion is isolated within thepockets.

An example of a voidform system with non-degradable components is apartially plastic voidform product by VoidForm® called StormVoid™ whichhas plastic elements that do not deteriorate like the standard cartonSureVoid® products. This means the structural elements (i.e. slabs,grade beams, etc.) must be designed for the potential uplift pressuresthe form is capable of exerting.

Another example of a voidform system with non-degradable components inthe prior are involves the use of a metal wire mesh formed into avolumetric shape as produced by SuperVoid Systems, LLC. In one theory,volumetric changes in the soil could cause the soil to push on the wiremesh, in turn causing the mesh to deform or the soil to push through themesh. This means the structural elements (i.e. slabs, grade beams, etc.)must be designed for the potential uplift pressures the form is capableof exerting. If a version of the SuperVoid product is used with ahorizontal layer of oriented strand board or plywood at the top of thewire mesh, the oriented strand board or plywood is degradable and canlose strength over time, but this is not problematic in and of itselfwhen the SuperVoid system is used as a slab voidform because the slabwill have cured by the time the wood material decays.

As there are many advantages with slab-on-voidform foundations, giventhat non-degradable voidforms can be used where degradable voidforms arenot practical due to a wet climate, the primary disadvantage of theslab-on-voidform foundation type has been that there is no methodavailable in the prior art of sufficiently protecting under-slabutilities from volumetric soil changes in a subgrade.

With regard to the protection of under-slab utilities underslab-on-voidform foundations, many slab-on-voidform foundations todayare constructed with under-slab utilities being supported by and buriedin a subgrade of expansive soil even though there is a known risk thatvolumetric soil changes could cause damage to a facility. The primaryreason that under-slab utilities are still soil-supported is that atechnology has not yet emerged in the prior art which provides completeisolation of the utilities from potential volumetric soil changes. Evenif access to the under-floor space was provided, because the voidformsdo not degrade quickly enough for workers to access an under-floor spacewithout removing the voidforms or because non-degradable voidformsobstruct such access and would require removal, which would be anarduous task, the industry has not yet developed a method ofconstruction with the necessary apparatuses so as to suspend under-slabutilities before a concrete slab of a slab-on-voidform foundation ispoured. While there are some disagreements between designers on therelative merits of the theories applied when non-degradable voidformsare used to isolate slabs of a slab-on-voidform system, with regard tovarious specific types of non-degradable voidform systems, there is ageneral consensus among design professionals of all design disciplinesthat absolutely none of these systems are appropriate if non-degradablecomponents of a voidform system can cause soil to impart forces,directly or indirectly through the non-degradable components.

Section 506.1 of the 2021 International Property Maintenance Code(IPMC), for example, requires where it is adopted locally that “Everyplumbing stack, vent, waste and sewer line shall function properly andbe kept free from obstructions, leaks and defects.” And, for example,only a small amount of movement from volumetric soil change is all thatit can take to cause a P-trap to crack just enough that the water in theP-trap spills out allowing noxious gases from a sanitary sewer system toenter an occupied space. There have been numerous lawsuits around thecountry that arise when plumbing is damaged from volumetric soil changesoon after a building is occupied and under-slab utilities fail invarious ways, especially when owners realize the magnitude of the costrequired to repair the under-slab utilities as they can be required bybuilding code to repair. The costs of repairs are so significantbecause, unlike with a slab on grade or a crawlspace, there is noconvenient access to the under-slab utility locations needing repair.One reason it is so expensive to repair an under-slab utility under aslab of a slab-on-voidform foundation is that it is often required tosawcut temporary access openings in the slabs at the intersection of twolines with each line being approximately at the midpoint between agridline of deep foundation elements such as drilled piers, thenexcavate by hand to dig laterally and find all locations where plumbingneeds to be repaired, often having to walk wheelbarrows of dirt out of abuilding and dump it outside. If one were to sawcut immediately over anydamaged utility location, sawcutting through a typical two-waystructurally suspended reinforced concrete slab of a slab-on-voidformfoundation, one could easily cause the slab to collapse as they sawcutthrough portions of the slab between piers that are necessary forstructural stability and this does happen from time to time in theindustry by accident when contractors think a slab is a slab on groundbut find out too late that it is a slab-on-voidform system. Owners areeven more angry when they find out that the repairs will not prevent theproblem from happening over and over again, potentially, over the lifeof the facility. Designers in areas where expansive soil often discussthis primary disadvantage of a slab-on-voidform system with Ownersbefore construction, noting that Owners could select a crawlspace optionfor additional cost if they want the ability to access and even toisolate some portions of the plumbing; however, most owners areunfortunately short-sighted in authorizing a slab-on-voidform system asthey are focused on the short-term goal of trying to maximize the floorplan area for their facility's program with a given budget.

For example, in March 2021, the Geoprofessional Business Association(GBA) has published a case study, Case History Number 108, of a $25Million damage claim made by an owner of a senior-living facility inColorado in which slab-on-voidform construction was used whereunder-slab utilities were not sufficiently isolated from expansive soilthat damaged the under-slab utilities. About four years afterconstruction was completed and the building was occupied, sanitarysewers began backing up and a powerful stench was permeating thebuilding and the walls and lower-level slab began to show heavingdistress. The owner had to move residents out of the building and intosuitable temporary housing and they eventually paid a contractor toexcavate under the building and install a crawlspace.

As another example, in the United States Court of Federal Claims, CauseNo. 09-672C, filed Sep. 7, 2012, which involves a case where under-slabutilities under a slab-on-voidform foundation were damaged by expansivesoil because the under-slab utilities were not sufficiently isolatedfrom the damage that expansive soil can cause, the court ruled that themechanical engineering firm “ . . . had a duty to isolate the plumbingfrom the expansive soil in a way that would accommodate the maximumpotential soil heave predicted in the soils reports,” noting that “ . .. whether willful or not . . . ” the mechanical engineering firm “ . . .failed to heed the warning and guidance set forth . . . ” “ . . . in thesoils reports' prediction that the soil could heave . . . ” “ . . . andprovided a negligent design in violation of the Contract.”

As early as 2007, the Foundation Performance Association (FPA) publisheda recommendation in their SC-11-0 publication titled Specification andApplication of Void Spaces Below Concrete Foundations that “Expansivesoils should not support under slab utilities below a Structural Slab”where the industry often refers to a slab of a slab-on-voidformfoundation as a structural slab. The publication further states, “Underslab piping must remain stationary with respect to the slab. Thedistance between the slab and the buried utilities may change as thesoil moisture changes. These changes could cause the utility lines todisconnect, start leaking or otherwise fail. There are various methodsto accommodate such differential movement by using designs that allowthe utilities to adjust to the changing conditions. The piping designbeneath the foundation must take into consideration the differentialmovement between the interior stationary piping and the soil outside thefoundation, and any associated bending stresses.” The SC-11-0publication even includes a diagram that diagrammatically shows a hangerassembly, including a traditional clevis hanger supporting an under-slabutility pipe, but the diagram shows the hanger to be either supported byrebar or to be supported by a concrete slab after it is poured andcured, both of which are impossible because the diagram shows both theslab and the rebar being supported by voidforms which are still intactwhich means that there is no access to install the utility pipe afterthe slab is poured and it means there was no support to install theutility pipe before the slab was poured. Additionally, the diagram doesnot show any means for retaining the soil on either side of a utilitypipe. The discussion and diagram show the disconnect between what isdesired and what limited technology was available in the prior art in2007. In a 2014 revision to the SC-11 document, numbered SC-11-1, theFPA did not change any of the text cited but even with a revised detailthey showed a scenario that is impossible to construct for reasons citedabove. Their reference to “various methods to accommodate suchdifferential movement by using designs that allow the utilities toadjust to the changing conditions” is referring to what some in theindustry refer to as flexible joints, such as a flexible expansionjoint. The FPA's recommendations have been made as a community ofprimarily geotechnical and structural engineers with the best of intentbut with little to no involvement from plumbing designers or contractorsthat could point out the disconnect in what they are recommending andwhat construction methods are in the prior art. For example, the problemwith a sanitary sewer plumbing design that incorporated flexibleexpansion joints all along the length of an under-slab utility is thatmost sanitary sewer systems function by a gravity system that has toslope downward at a minimum slope along the entire length of theplumbing system and, in addition, plumbing codes require specificminimum slopes, so it is not technically feasible to have an underslabutility system with so many flexible expansion joints slope sodramatically that at any point under a slab the subgrade could heaveand/or fall without causing a negative slope that would cause thesanitary sewer system to no longer function properly, and furthermorethe cost of so many flexible expansion joints would cost more than acrawlspace foundation in many cases such that, even if it weretechnically feasible for a specific case, it would most likely not be alogical approach compared with a crawlspace foundation. As anotherexample, SC-11-1 diagramatically shows a soil retainer system that hasno means of stability to retain the soil.

There have been several attempts to invent methods and apparatuses witha goal being to attempt to isolate under-slab utilities from expansivesoils. However, all of these attempts have failed in one form or anotherto provide an actual means of isolation. When the Structural EngineersAssociation of Texas (SEAoT) became aware of the concept behind some ofthe disclosed inventions for novel ways to isolate under-slab utilities,it quickly assembled approximately a dozen engineers includingstructural engineers, geotechnical engineers and mechanical engineers toreview available technologies and make recommendations because theyrecognized that none of the prior art has been able to sufficientlyisolate utilities and utility supports from expansive soil, in contrastto embodiments of the invention disclosed herein. In January 2021, basedon the recommendations of the aforementioned group of engineers, SEAoTsubmitted to the International Code Council (ICC) a code change proposalto the 2024 International Plumbing Code (IPC) that would require ansufficient means of isolating under-slab utilities from expansive soilunder slabs that are isolated, consistent with this invention, and wouldprohibit the majority of prior art methods as they do not sufficientlyisolate under-slab utilities. One exception in the prior art is that itwould remain permitted to install plumbing and supports after the slabis poured by removing voidforms and post-installing anchors overhead,which is in the prior art but is often thought to be cost-prohibitivefor new construction. SEAoT submitted a 14 page document to ICC with therationale for their proposed code change. The SEAoT document isavailable at athttps://www.iccsafe.org/products-and-services/i-codes/code-development-process/2021-2022-group-a/and is hereby incorporated by reference as if fully set forth hereinherein. At the International Plumbing Code Committee Code ActionHearings, SEAoT's proposed code change was supported by testimony fromvarious mechanical and structural engineers, the GeoprofessionalBusiness Association, the American Institute of Architects and theAmerican Council of Engineering Companies of Texas. The 2024International Plumbing Code Committee then approved the proposed codechange, with some modifications that SEAoT supported that clarified theintent of the proposed code change. And, the change will be a part ofthe 2024 International Plumbing Code when it is published. Whilenumerous serious attempts have been made in the last several decades,the prior art methods, as described above, do not meet the requirementsfor isolation as will be set forth in the 2024 IPC.

It may be important to note that, while the United States Court ofFederal Claims indicated in the case cited above that the mechanicalengineering firm was negligent in designing a soil-supported under-slabutility under a slab-on-voidform foundation for the specific project atissue, there were approximately a dozen engineers assembled by theStructural Engineers Association of Texas, including structuralengineers, geotechnical engineers and mechanical engineers, which allindicated in their collective rationale statement to ICC that designinga soil-supported under-slab utilities under a slab-on-voidformfoundation was within the standard of care for each of those professionsin Texas as of January 2021 when the statement was issued to ICC. Thestandard of care may change over time to exclude this practice, but thispractice is still being used today.

And, while some building officials might interpret current coderequirements to prohibit soil-supported utilities under slab-on-voidformwhere expansive soils are present, the only interpretation of codeprovisions that applies to any specific project with regard to codecompliance is the opinion of the building official with the AuthorityHaving Jurisdiction (AHJ) for that project. There are many projects inTexas where building officials issue building permits without taking anyexception to soil-supported under-slab utilities under aslab-on-voidform or a crawlspace foundation, even when they are provideda copy of a soil report indicating that expansive soils are present anddocumentation indicating that there will remain some potential verticalmovement of the subgrade after the building is occupied.

Prior art systems for vertically supporting utilities (including but notlimited to sanitary sewer piping) that are designed to be located understructurally suspended concrete slabs over void forms (including but notlimited to carton and plastic void forms) bearing on other foundationelements (including but not limited to piers, piles, caissons. footings,and grade beams) without a typical crawl-space access include systemsthat directly bear on soil within the active zone (“Direct BearSystems”). In these systems the utilities are laid down directly on topof the soil in the active zone or on top of material (including but notlimited to coarse aggregate (rocks), fine aggregate (sand), cementedsand, flowable cementitous fill, road base, lime-stabilized earth) thatis laid down directly on top of the soil in the active zone.

The prior art also includes systems that indirectly bear on soil withinthe active zone (“Indirect Bear Systems”), in which utilities typicallyhang from above by a threaded rod that is supported by a primary nutbearing on the system (e.g. prior art systems known as PlumbingVoid® andPipe-Void) which is bearing on soil within the active zone or othermaterial that is bearing on soil within the active zone. The threadedrods typically extend up into the thickness of the concrete slab withsome form of anchorage (including but not limited to a secondary nut) sothat the slab can act as another support; however, the primary nut staysin place and is not removed because the operations of pouring theconcrete slab and allowing it to cure prohibit any kind of convenientaccess underneath to remove the primary nut. Indirect Bear Systems donot have a reliable means of avoiding the risk that expansive soil coulddamage under-slab utilities; and, there can even be a risk of a muchlarger amount of damage than with Direct Bear Systems if any hangers incontact with soil corrode and pipes fall or if any soil retainingsystems fail and pipes shift dramatically.

Both Direct Bear Systems and Indirect Bear Systems can allow volumetricchanges (vertically and horizontally) in the active zone to cause forcesto bear on the utilities which can cause the utilities to shift(including but not limited to deflecting up or down over certain regionsof utility piping, breaking utilities, or causing them to leak). TheIndirect Bear Systems are not capable of resisting the forces likefoundation elements such as drilled piers, driven piles and sufficientlydeep footings. When utilities shift too much, the utilities cannotfunction properly. For example, sanitary sewer piping typically requiressewage flow downhill and any portions that bend after construction, inany direction, can cause sewage to not flow properly. Even if flexiblejoints are installed in these utilities, the pipes themselves (includingbut limited to PVC, cast iron and ductile iron piping) are typically notcapable of flexing as much as they may need to flex and maintain apositive slope for drainage. Unlike maintenance of sanitary sewer undercrawl-space and slab-on-grade type foundations, maintenance of utilitiesis relatively difficult and expensive because convenient access directlyto or directly above the area of concern cannot be provided, andIndirect Bear Systems often create additional obstacles to such repairs.

It is, therefore, desirable to have a system that does not bear(directly or indirectly) on any soil within the active zone but ratherbears on structural elements that are bearing on soil below the activezone and/or are designed to sufficiently resist the vertical forcesassociated with volumetric changes in the active zone by virtue of theirpenetration below the active zone.

Additionally, Indirect Bear Systems are generally proprietary systemswhich require relying on components of the system to retain soil so thatsoil does not fall, slide, push, deflect, rotate, or otherwise eitherdirectly cause forces on the utilities or indirectly by means ofbecoming a shim where a void was intended (including but not limited tounder the utility piping, above the utility piping, on either sideadjacent to the utility piping, and related to any permanent systemelement such as saddles and hangers) to isolate the utility frompotential soil-related forces, which can cause utilities to no longerfunction as intended and require relatively expensive maintenance. Onereason these systems typically require that the proprietary componentsretain soil is that the systems are too wide for the main layer of voidforms (immediately under the slab) to structurally span over them andreliably support rebar, workers, and wet concrete until the concretecures. The problem with these proprietary retaining elements is thatthese systems have not been designed by structural engineers and thereis insufficient evidence that they can reliably retain soil afterconstruction for many common conditions which are necessary for typicalconstruction. For example, a horizontal layer of plywood supportsseveral feet of soil in the SuperVoid system. And, as another example,½″ thick plastic retainer boards with the manufacturer claiming thatthey are acceptable to a depth of 8 feet but the height of the soil tobe retained in not limited, which could lead an installer to install aretaining wall that is 8 feet tall made entirely out of ½″ thick plasticretainer board and these systems can fail.

Therefore, there is a need for a system that allows soil retainageaspects to be designed by qualified design professionals for eachspecific application, using methods in the prior art (including but notlimited to temporary vertical cuts in cohesive soil where there is anacceptable factor of safety, sloping the grade to an acceptable stableslope such as the angle of repose for cohesionless soils, and installingpermanent concrete retaining walls that become buried underground but donot extend above the bottom of the main layer of void forms immediatelyunder the concrete slab).

Also, Indirect Bear Systems are typically buried under soil as utilitylines elevations vary in depth below the slabs, which exposes the hanger(typically a threaded rod) to soil which can corrode the hanger overtime if it is made of a corrodable material. The main reason that thesesystems are buried is that, since they are too wide for boxes above tospan over them, they have to support soil above them and retain soiladjacent to them and therefore it is desired to have the soil retainingelements span as short a distance as possible. If the hanger corrodessufficiently, it can cause the support system to fail which can causethe utilities to not function and require relatively expensive repairs.The primary nut typically needs to only support empty piping before theslab is poured. After the slab is poured and cured, as piping is filledwith fluids and emptied during occupancy, the hangers support a largerload than the system supporting the primary nut was designed to supportand the hangers begin to support a dynamic (not static) load which cancause failure of hangers upon jarring. Under occupied conditions, thesehangers can fail if corroded.

It is, therefore, desirable to have a system that does not allow soil tocontact any of the hanger assemblies. Furthermore, generally corrosionresistant materials such as fiberglass, aluminum, stainless steel andgalvanized steel are available with for use in this invention to resistany ambient sub-slab moisture for an even longer useful life expectancy.

Also, since Indirect Bear Systems retain soil, the inspections requiredby the building code are hindered by the soil retaining components ofthose systems.

A desirable solution, therefore, allows full inspection of piping asrequired by building codes.

In Indirect Bear Systems, because they retain soil, there is notsufficient height in the systems to accommodate a sufficiently longhinge pipe with void space underneath, a rotating joint at the end ofthe slab-hung length of utility piping and a rotating and telescopingjoint at the soil-supported end of the hinge pipe to transition betweenthe two systems at the exterior of the grade beam. This arrangement isnecessary so that, if the potential vertical movement occurs upward, theutility piping will not slope less than the minimum permitted byapplicable regulations. If the potential vertical movement downwardoccurs, then the utility piping will not exceed any maximum slopepermitted by applicable regulations.

It is, therefore, desirable to have as system that allows independentsoil retaining systems so that a hinge pipe can be installed tosuccessfully transition between slab-hung and soil-supported sections ofutility piping and can utilize rotating and telescoping joints availablein the prior art.

Also, Indirect Bear Systems are difficult to access after constructionif it is necessary to maintain them.

It is, therefore, desirable to have a system that avoids the need formaintenance associated with damage caused by expansive soil, which canhappen in the prior art as noted above. It is also desirable to have asystem that allows independently designed soil retaining systems so thatdesign professionals can create sufficiently large void spaces along thesides of the utility piping that can be more-easily accessedhorizontally through openings in exterior grade beams by removingexterior backfill (rather than cutting temporary access openingsvertically into the slabs and hand-digging from the opening to pipelocation which can often be far from the nearest potential location fora temporary slab opening).

An example of an Indirect Bear System in the prior art device aimed ataddressing the issue of damage caused by expansive soils is thePlumbingVoid® product by VoidForm, which includes a unit having aplurality of members that, when used in combination, is intended tocreate a self-contained void space for the safe routing of plumbinglines, electrical lines and other conduits underground. The unitincludes a plurality of selectively arrayed panel sections coupledtogether to form a routing path. The panel sections are supported with aplurality of braces/connectors for stability. Additional panels may beadded over the top of the panel sections so as to enclose the space.Pipe is laid within the space and elevated as necessary to ensure properdrainage. Elevation is secured through the use of a clevis bracket andthreaded rod configured to extend out through the space and panelsections. A fastener and washer combination is used to provide temporarysupport for the pipe being supported by the braces/connectors. Bymodifying the panel sections, routes may be customized to accommodateplumbing needs. However, this system does not isolate the utilities fromexpansive soil because it is an Indirect Bear System and, as noted bySEAoT in their 14 page rationale statement supporting their proposedcode change to prohibit Indirect Bear Systems, the PlumbingVoid productdoes not sufficiently isolate utilities from expansive soil. A commonPlumbingVoid detail that has been used has interior spacers “above orbelow pipe” which can contact the pipe and impart loads onto the pipingif the soil swells or shrinks and causes the box to shift up or downmore than the gap between the pipe and the interior spacers. No specificelevation for the spacers is provided on the detail and specifierstypically do not specify any clearance dimension above or below thepipe. The purpose of the spacers is to provide an intermediatebracepoint for the retaining boards, which are not designed by anEngineer for the site conditions in the standard product, to preventexcessive deflection which could pinch the pipe and cause damage. Forthis reason, the interior spacers are typically near the piping and sothis is a legitimate concern. In addition, the U-bars at the bottom areoften bare steel without any protective coating and in contact with soilsuch that they could corrode and fail even though they are structurallynecessary to keep the two vertical retainer boards separated enough sothat they do not fail and pinch the pipes, which could cause the pipesto break. It has been suggested that a “knife-edge” will occur so thatno load will push the box up from the bottom; however, SEAoT indicatesthey believe this is an incorrect theory because, while soil does expandwhen it gets wet, expansive soil does not become a fluid as is evidencedby the fact that it has sufficient internal compressive strength toimpart significant upward pressures and a layer of dry soil cannaturally occur over a layer that becomes wet such as with deep seatedswell that has been observed in many forensic investigations. ThePlumbingVoid® Washer is a large washer that is intended to fold inbetween two U-Bars when the box is pushed upward when soil swells. Untilthis folds, there is a load imparted onto the hanger so that it couldbuckle the hanger, especially if the hanger is about 7 feet long as themanufacturer's detail indicates it is applicable with trenches that are8 feet deep. If the rod does not fail, the rod will impart load onto theslab that the slab must be designed for. A Structural Engineer designingthe slab would need to know the locations of these hangers and designthe slab to resist these loads. If the soil shrinks, the soil above thebox would weigh down the top of the box, which would not allow failureof the washer and this would create an additional tension on the hangerwhich it was not designed for. Failure of the rod in tension could causethe plumbing to shift downward and break or require maintenance. If thesoil shrinks, the bottom and sides of the box would shift down with thesoil whereas the top could be suspended at the original installationelevation. If the vertical legs of the top U-Bars are not long enough,the bottom of the box could slide down enough that the top U-Bars nolonger provide sufficient lateral bracing of the vertical retainerboards. If the tops of the vertical retainer board fall inward, theshifting elements could break the plumbing and/or cause shifting thatrequires maintenance. A ½″ thick retainer board is shown typically oneach side where the detail indicates there could be 8 feet ofhydrostatic soil load from a cohesionless strata; if this retainer boardis not thick enough to resist the lateral soil pressures at the depthsinstalled, the retainer board could fail inward and damage a utilitypipe. The detail calls for soil to be backfilled against the retainingboards, but equipment loading can be significant. Also, there does notappear to be any typical specification expected for lateral movementassociated with swelling in a typical detail that has been used inindustry. Swelling of expansive soil is a three-dimensional phenomenonand some lateral movement should be expected which may cause the pipesto pinch and break or service disrupted if there is not sufficient spaceon each side of the clevis hangers. In applications where thePlumbingVoid® product has been used, the product may not have hadsufficient vertical leg length of the U-Bar, minimum clearance above andbelow the piping, minimum load capacity of the sacrificial washer tosupport plumbing during initial installation, and maximum ultimate loadcapacity of the sacrificial washer. A threaded rod and clevis support isshown in the typical detail to be in contact with soil that could causecorrosion if the Mechanical Engineer specifies steel unless it isprotected in an approved manner or made of fiberglass. If the hangerand/or clevis support corrodes, the plumbing may shift downward and needmaintenance in an area where maintenance is difficult to access.Mis-installations have been encountered in industry indicating that itis difficult for a plumber to understand the structural and geotechnicalsignificance of the small details associated with the customization ofthe generic assembly for a specific application, thereby foiling theattempt to properly partially isolate the plumbing even further.

Another example of an Indirect Bear System in the prior art device aimedat addressing the issue of damage caused by expansive soils is thePipeVoid System manufactured by SuperVoid in which an expanded metallath shape supports oriented strand board or plywood under an under-slabutility pipe that is buried in soil over the apparatus. This soil isplaced on top of the SuperVoid product and plumbing is placed on thatsoil, with hangers extending vertically to be received by the slab whenthe slab is installed. If expansive soil swells under the assembly, thesoil can cause the SuperVoid product to lift up, which would cause thesoil to lift up, which would cause the plumbing to lift up in places.This uplift can be contrary to the hanger and clevis support which cananchor the pipe at a fixed location at supports, causing distortion insanitary sewer lines that may cause clogs or break the lines. TheSuperVoid product is comprised of expanded metal lath and plywood. It isnot likely that the expanded metal lath would corrode sufficiently soonafter occupancy. Some have claimed that these products cannot transferload because they form a “knife edge” where the soil splits as itheaves. This is an invalid theory which assumes soil is a fluid whenexpansive soil is associated with moisture migration through partiallysaturated soils that can leave soils near the surface relatively dry assoil deeper down in an expansive strata swell as a “deep seated swell”.In reality, just as expansive soil has proven to push piping up whenburied, expansive soil can push up on any material. The pressurerequired to resist all swell in these circumstances if often thousandsof pounds per square foot; the metal lath product is not sufficient toresist these loads. If the expanded metal lath compresses like a spring,there still is load that is transferred upward that the plumbing is notdesigned to accommodate. And, many Mechanical Engineers do not have thetraining or experience to predict what the stresses and strains in theplumbing would be under these circumstances, much less verify that theywill not damage the piping or interrupt service. In addition, ifexpansive soil swells on each side of the assembly, the soil can causethe plumbing to lift up in places. A typical detail used for the productcalls for cohesionless, granular material; however, expansive soilswells laterally and upward, which can cause compression arches to formand transmit load onto the piping, even in cohesionless, granularmaterial. Furthermore, this approach uses plywood to retain the soilabove a voidspace but the plywood may decay over time and cause the soilto cave in under the piping, which could allow expansive soil swellingto push pipes upward, even though the hangers and clevis system wouldresist this upward movement, and also create the plumbing problemsdescribed above. If the rod does not fail in buckling, the rod willimpart load onto the slab that the slab must be designed for. AStructural Engineer would need to know the locations of these hangersand verify that the slab can resist these loads. If the soil shrinks,the soil above the plumbing could drag down the plumbing which is atfixed elevations at each hanger, which could require maintenance. Theplywood is covered on top with a covering, but the bottom is exposed tomoisture from the subgrade, which is typically sufficient to degradecarton voidforms soon after construction. In addition, the soilretainers are shown to sit on the ground when installed and not have anyextension buried below the trench subgrade. If the expanded metal lathdoes corrode, the plastic soil retainers on each side do not havesufficient resistance at the bottom to prevent lateral movement causedby soil loading, which could cause material to fill into the proposedvoidspace. A galvanized threaded rod and clevis support is shown incontact with soil that could cause corrosion. If the hanger and/orclevis support corrodes, the plumbing may shift downward and needmaintenance in an area where maintenance is difficult to access.

Another example of an Indirect Bear System in the prior art device aimedat addressing the issue of damage caused by expansive soils is thePipeVoid System manufactured by SuperVoid in which an expanded metallath shape supports oriented strand board or plywood over an under-slabutility pipe, wherein various soil materials are installed over theoriented strand board or plywood. In this application, many concerns aresimilar to those expressed for the above example with the PipeVoidproduct under the under-slab utility pipe. In this application though,there is a SuperVoid product which provides no voidspace above theplumbing in case the soil shrinks. In this version of the typicaldetail, it is possible for the plywood to decay at the initialsuspension nut which would theoretically allow the system to slipupward. However, a threaded rod as part of a hanger assembly could causecompression on the hanger that could cause it to buckle, especiallygiven the note on the typical detail to not compact soil above theplywood. In this typical detail, the plywood deteriorating could allowsoil to fall down under the piping and fill in the voidspace, whichwould allow expansive soil to heave and cause the plumbing to shiftupward. If the soil shrinks, the soil above the box would weigh down thetop of the box, which would create an additional tension on the hangerwhich it was not designed for. Failure of the rod in tension could causethe plumbing to shift downward and break or require maintenance. Theredoes not appear to be any specification in the detail accounting forlateral movement associated with swelling. Swelling of expansive soil isa three-dimensional phenomenon and some lateral movement should beexpected which may cause the pipes to pinch and break or servicedisrupted if there is not sufficient space on each side of the clevishangers.

Yet other examples of Indirect Bear Systems in the prior art arespecified on construction documents issued by Mechanical Engineers, suchas installing a strut channel over a narrow trench with a hangerassembly suspended by the strut channel. The soil can collapse into thetrench because there is no retaining structure. And, additionally, thechannel is bearing on the subgrade which can rise or fall withvolumetric soil change, which would cause the loads to transfer to thenut supporting the hanger assembly that would then cause the load totransfer into the slab. The slab would need to be designed for this loadand, more importantly, the load can cause the threaded rod of the hangerassembly to buckle, causing the utilities to shift and no longerfunction as intended.

There is, therefore, a need for a system that provides adequateisolation of under-slab utilities from volumetric soil changes underslabs of slab-on-voidform foundations for many project types ingeographic locations where soils undergo volumetric changes afterinitial construction of a project is complete.

Also, when foundation systems are isolated from expansive soil movementby voidforms or crawl spaces, if one attempts to isolate any slab-hung(at essentially a constant elevation) under-slab utilities (includingbut not limited to sanitary sewer systems, domestic water lines, fireprotection lines, roof drains, natural gas lines, electrical conductors,telecommunications systems, etc. . . . ) from expansive soil, it isnecessary to successfully transition utilities to a soil-supportedutility condition at the building perimeter.

One challenge to transition when applied to a crawlspace foundation isthat, because the site beyond the perimeter of a crawlspace foundationtypically has expansive soil which can cause problems as systems musttransition from a building condition to a site condition. Consequently,it is common for sanitary sewer plumbing systems to be installed whereinthe under-slab plumbing near the perimeter is not hung over anunder-utility space but rather buried in the subgrade because mainsanitary sewer lines which serve the under-slab utility line aretypically very deep considering that traditionally sanitary sewersystems operate by gravity flow where possible. Where under-slabutilities under crawlspace building foundations are not isolated, whichcan often extend very far into the interior of a building where aprogressively deep sanitary sewer main is installed under a building tocollect wastewater from many fixtures, expansive soil often causesdamage to the under-slab utilities needing repair. Crawlspacefoundations are required by the many building codes to have access andventilation. Where such access and ventilation are provided, it ispossible to dig up a buried utility line and repair the line, but clearheight conditions are often extremely limited to make the constructionas economical, making these utility repairs sometimes more expensivethan with a slab-on-grade system, and the repairs are not necessarilypermanent because the underlying cause of the problem can continue overand over again with time.

Flexible expansion joints have been used in the prior art, such as thosedescribe in IAPMO PS 51, Industry Standard for Expansion Joints andFlexible Expansion Joints for DWV Piping Systems as published by theInternational Association of Plumbing and Mechanical Officials (IAPMO),in which DWV Piping refers to drain, waste and vent piping used insanitary sewer systems. A flexible expansion joint can have atelescoping fitting that allows axial contraction and elongation with arotating fitting at each end wherein each end rotates, with internalgaskets that can be suitable for sanitary sewer systems and a differentarrangement of internal gaskets that can be suitable for pressurizedwater applications such as domestic water or automatic fire sprinklerwater supply pipes. Thus, flexible expansion joints can allow one end ofthe fixture to be at a constant elevation while the other end can liftor drop vertically, and in theory they can lift or drop the magnitude ofthe potential vertical movement caused by volumetric soil changes.However, there are challenges with installing such a fixture.

For example, if the flexible expansion joint is buried in soil,expansive soil may cause damage to the length of the pipe betweenrotating ends, which the pipe is not designed to withstand.Additionally, if the flexible expansion joint is buried in soil, it willreduce the useful life of the fixture compared to unburied conditionsbecause it is has moving parts in soil. Over time, through cyclicalflexing, soil particles can intrude and interfere with the intendedoperation of the moving components. If the flexible expansion joint isburied, it cannot easily be inspected during the life of the facilityand replaced as needed. In fact, applicable regulations require certainfixtures like this be accessible for this reason. Also, if the flexibleexpansion joint is not buried, one end will need to be soil supported.At the soil-supported end, to successfully isolate the fixture fromexpansive soil, the soil needs to be retained so that the soil does notencroach on the clear vertical distance required under the length of thefixture to allow for the soil to rise the estimated potential verticalmovement. The retaining structure, however, cannot be part of thefoundation but must rather be soil-supported and allow for the estimatedpotential vertical movement up or down. At the building perimeter,however, there needs to be a foundation element such as a grade beam,which is to remain at essentially a constant elevation. If one were tosimply have soil-supported piping outside of the building extending froman unfilled trench through a vertically slotted hole, the weight of thefixture when being installed or replaced could cause a structuralinstability which would lift the soil-supported pipe, causing it torotate which could damage the plumbing and possibly cause injury.Furthermore, in the conditions for the case described above, anypressure on the piping up or down would cause the pipe to push up ordown on the soil-retaining system, which can damage the pipe. Also inthese conditions, any footing/counter-weight to address or pipeprotection system to address issues could change the potential verticalmovement of the soil at those elements, which could cause a negativedrainage scenario (where water drains to the building instead of away,potentially causing more vertical movement than originally estimated) ifthe soil at the plan locations of such system has a lower potentialvertical movement than the soil around such system. Also, any systemssuch as those described cannot be bonded to the utility line, which mayneed to be replaced over the life of the facility. Also, mechanicalengineers typically design and specify utilities up to 5 feet from thebuilding perimeter with civil engineers specifying the work beyond, andthere is a desire to keep any kind of transition system within thisboundary so as to stay within the scope of a single design disciplineand avoid the expensive miscoordination that can occur if a site utilityplan is designed assuming utilities can be run without consideration ofa transition system up to 5 feet away from a building perimeter andthere is a conflict discovered after installation of site utilitieswhich requires that an entire site utility system be removed andreplaced simply because the industry commonly understands the basicscope of a mechanical engineer designing utilities to end 5 feet awayfrom a building.

Furthermore, methods in the prior art for clamping, such as a standardpipe clamp and standard pipe strap are not sufficient for clamping ontoa non-structural pipe and mounting it onto a perpendicular concreteelement such as a gradebeam with an over-sized hole so that the clampcan resist axial forces in either direction, transverse forces, andmoments to allow a non-structural pipe such as a pvc sanitary sewer pipecan cantilever out to support an end of a flexible expansion joint,especially not a clamp in the prior art that can also be adjusted andremounted.

In the prior art, a standard clamp consists of two halves that arebolted together and, when bolted together, they form a circular openingthat can be clamped around a pipe. Each half of the standard clamp hasflanges that extend so that, for example, a vertical pipe can be clampedand supported vertically on a horizontal surface but this does notresist upward movement on the pipe and it does not resist transversemovement. In general, it is not typically necessary to anchor anythingto a standard clap because the pipe itself can be supported and bracedas necessary. In and of itself, a standard clamp is not capable of beingbolted to a surface that is perpendicular to the pipe unless potentiallybolts are inserted in between gaps between the two halves of the clamp,and in this case the distances of the bolts from the pipe in standardconfigurations are generally not sufficient to avoid reinforcement in aconcrete element and have sufficient edge distance to comply withminimum building code requirements or to provide a sufficiently largeenough diameter bolt to be capable of resisting the required forces. Forexample, most building codes require that plumbing be isolated from anyelements with felt or a gap so that the plumbing can be removed andreplaced over time if necessary, and the oversizing of the hole for thisalone can make it difficult for bolts through the gap between halves ofa pipe clamp to be successful, and if the pipe elevation needs to beadjusted after mounting it is likely that the new location willpartially overlap with the old bolt and make it necessary to core outthe old bolt and make the remediation even more expensive.

A standard pipe strap is a method of mounting a pipe to a surface,however it is only suitable for mounting a pipe that is parallel to aconcrete face whereas a pipe needs to cantilever out perpendicular froma foundation element to support a flexible expansion joint in thisinvention. In the prior art, attempts have been made to try togeometrically arrange a concrete face in parallel with a pipe and use apair of standard pipe straps so as to accommodate the need forresistance to axial forces, transverse forces and moments and provideconstruction tolerance in vertical elevation, however such attemptsrequire an elaborate geometry be constructed with a concrete protrusioncantilevered from a foundation for this purpose and the field toleranceson the plan location of such a parallel face must be relatively precise,and this approach has proven difficult in the field because it is notadjustable.

Another problem is that attempting to fabricate some kind of brace inthe field raises other concerns. For use with a system that protectsplumbing under a slab of a slab-on-voidform foundation, it is necessaryby some building code provisions for components subject to corrosion tobe protected in an approved manner and not simply be unprotected steel.If a standard pipe clamp is modified in the field by welding it to asupport element such as a steel component that is galvanized, thewelding process will destroy the galvanized coating that protects thesteel from initial corrosion. If a standard pipe clamp is modified inthe field by welding it to a support element such as a component that isstainless steel, the welding process will be expensive because astainless-steel welding operation will need to be set up on a project.Furthermore, it may be difficult to get proper access to do welding, fora welding rod to reach where it needs to reach, and for properinspection of a weld between a standard clamp in the field and any othercomponent used in an attempt to stabilize a standard pipe clamp. Plasticcomponents can break in the field if overstressed during installationand/or field modification.

There is, therefore, a need for an improved method of transitioningunder-slab utilities of isolated foundation systems to soil-supportedutility conditions suitable for both crawlspace foundations as well asslab-on-voidform foundations.

Also, voidforms are not sufficiently rigid for a sufficient time toprovide support to under-slab utilities under slab-on-voidformfoundations before the slab is poured. Therefore, utility suspensionsystems must bear on the ground. Foundation elements can do this, butthey are typically far apart so that a reinforced concrete slab can spanbetween them, which makes it an added cost to install a utility framingsystem that bears only on foundation elements. Any support that bears onthe ground itself is not acceptable if it can allow forces fromvolumetric soil changes to push/pull on utilities and/or foundations andcause damage.

Therefore, there is a need for a method and system whereby a framingsystem that is flexibly positioned and does not bear on the ground.

Also, it is necessary to retain soil when supporting under-slabutilities over a voidspace that extends below the main layer ofvoidforms under a slab-on-voidform foundation slab. And, it is commonthat under-slab utilities, and voidspaces under those utilities, need toextend below the main layer of voidforms if it is desired to effectivelyisolate them from expansive soil. Benching soil to retain this soil isproblematic because it is time-consuming to map out in 3 dimensionalspace how to retain soil to protect the distributing piping systems forunder-slab utilities which can be complex, and it is time consuming tograde the benched trenches to the proper elevation so that whenvoidforms are placed the bottom of the slab is at the correct elevation,and soil can slough off into the trench, requiring time-consuming,regular maintenance of the trenches as well as risking loss of supportfor the boxes above which could require either excavating a wider trenchor trying to reconstruct the sloped soil of the original excavation. Thetime required is a challenge in that it costs a lot for labor but alsochallenging in that carton voidforms often used in slab-on-voidformfoundations need to be placed on a dry subgrade and concrete pouredbefore a rain event occurs (to avoid deterioration of the cartonvoidforms which could cause the voidforms to collapse when placing freshconcrete, and it can be difficult to find sufficient dry periods in theweather to accomplish all that is needed when the sides of the trenchesneed to be benched. The only alternative to benching when the utilitiesare below the bottom of the main layer of voidforms is to install arelatively short retaining structure (often less than 4 feet in height)which can be more expensive than benching if methods of installing aretaining structure in the prior art are used. Retaining structures areexpensive to form with formwork and expensive in that they need toextend deep enough below the bottom of the utility trench so as tosufficiently resist overturning and sliding from soil pressures behindthe retaining structure as the building codes require retainingstructures have a minimum factor of safety of 1.5 against overturningand sliding. These type of retaining structures are typically concrete,reinforced with conventional rebar, that requires additional laborcosts, materials costs and time which increases the constructionschedule on a project. A challenge with utility trench walls underslab-on-voidform foundations is that the soil is typically a highlyexpansive clay, which the International Building Code deems “unsuitable”for use behind a retaining structure. Complicating and making retainingstructures in the prior art more expensive is the fact that expansivesoil can create very large lateral pressures on retaining structureswhen the expansive soil swells due to moisture content changes, andthere is wide disagreement within the Geotechnical Engineering communityon how great these pressures are, with some indicating that may bethousands of pounds per square foot. Many Geotechnical Engineersrecommend that all expansive soil be removed behind a retainingstructure and be replaced with less expansive “select” fill. There hasbeen litigation claiming engineers were negligent for allowing expansivesoil backfill behind a retaining structure but not accounting for theamount of rotation that can occur when these walls are embedded in theground, as is common in the industry. It is also expensive and risky tocut voidforms around intricate spaces of complex plumbing distributionsystems in the plumbing trenches. Manufacturers of such voidforms do notrecommend overly-cutting the forms because they are designed to collapsein their manufactured “whole” condition. The risk is that the voidformscould collapse when placing concrete.

Therefore, there is a need for an underslab utility suspension systemthat incorporates improved soil retention suitable for both crawlspacefoundations as well as slab-on-voidform foundations.

SUMMARY OF THE INVENTION

The present invention solves the above-described problems. In oneaspect, it provides a system and method of using a utility supportframing system for slab-on-voidform foundation systems. In anotheraspect it provides a method and system whereby a framing system forsuspending under-slab utilities can be flexibly positioned and does notbear on the ground. In another aspect, it provides a method and systemthat allows soil retainage employing vertical cuts in cohesive soil,sloping the grade to an acceptable stable slope, installing conventionalpermanent retaining structures and installing inventive mobile retainingwalls that are permanent concrete retaining walls that become buriedunderground but do not extend above the bottom of the main layer of voidforms immediately under a concrete slab so as to be capable of slidingwhen exposed to sufficient lateral expansion pressures from retainedsoil. The invention also provides a system and method for an under-slabutility suspension system that incorporates improved soil retentionsuitable for both crawlspace foundations as well as slab-on-voidformfoundations. In another aspect, the invention provides a method forsuccessfully transitioning utilities to soil-supported conditions at abuilding perimeter where a slab-on-voidform foundation or a crawlspacefoundation is used. In yet another aspect, it provides for an inventiveclamp and method of using the same where the clamp resists axial forces,transverse forces and moments, especially when a pair of the clamps areused in tandem, such as would be necessary for a pipe to cantilever outfrom a foundation gradebeam that is perpendicular to a utility pipe, andsupport one end of a flexible expansion joint. In yet another aspect,the invention includes an inventive protective utility counterweight foruse around a utility pipe so as to prevent the utility pipe frombreaking that is also sufficiently rigid to cantilever support of autility pipe through an opening in a foundation element, that resistsoverturning when it cantilevers support of a utility pipe through anopening in a foundation element, and that allows for removal andreplacement of a utility pipe.

For purposes of this disclosure, the term slab-on-voidform foundationmeans a foundation system, for a building, wherein there is a slablocated immediately above a voidform system and said slab is capable ofstructurally spanning over said voidform system after construction ofthe building is complete, without needing the voidform system to provideany means of structural support. The slab of a slab-on-voidform systemis the lowest floor at the floorplan area location of the slab, whereinoccupants can either walk directly on the slab or on a flooring systemthat is installed on top of the slab. The slab of a slab-on-voidformfoundation is primarily concrete and is reinforced with conventionalreinforcement bars or post-tensioned cables. Examples of buildings thatcan have slab-on-voidform foundations are government buildings, schools,churches, office buildings, banks, retail stores, parking garages,industrial buildings, agricultural buildings, storage buildings,multi-family facilities and single-family residences.

For the purposes of this disclosure, a slab of a slab-on-voidformfoundation is a reinforced concrete slab system that is installed overvoidforms and attached to foundation elements. As an example, many slabsof slab-on-voidform foundations are installed in stages, with a vaporbarrier placed on top of voidforms, then slab reinforcement installed onreinforcement supports that are placed on top of the vapor barrier, thenconcrete poured on top of the vapor barrier to encase most or all of theslab reinforcement. Where a vapor barrier is installed immediately undera slab of a slab-on-voidform foundation, the vapor barrier shall beconsidered a part of the slab. As another example, some slabs ofslab-on-voidform foundations are installed in stages, withpost-tensioning cables installed on cable supports that are placed ontop of voidforms, then concrete poured on top of the voidforms to encasemost or all of the slab reinforcement, then post-tensioning cablestensioned.

For purposes of this disclosure, a voidform system is a system that isstructurally supported by a subgrade and is capable of structurallysupporting a concrete slab of a slab-on-voidform foundation, wherein nopart of the voidform system is a foundation element, wherein no part ofthe voidform system is a framing system, wherein no part of the voidformsystem is a vapor barrier and related vapor barrier components, whereinthe majority of the voidform system is not manually removed after saidconcrete slab is installed, and wherein the system either partially orcompletely consists of a configuration of material that is:

-   -   degradable in that said configuration of material loses the        majority of its vertical compression capacity after said        configuration of material has been exposed to 100% humidity for        120 days, when compared to the vertical compression capacity of        the configuration of material with said configuration of        material when originally manufactured;    -   compressible in that the configuration of material compresses at        least ½ inch when a vertical compressive load is applied that is        equal to the tributary dead load of the slab plus the tributary        portion of the ultimate upward load capacity of the slab 28 days        after the concrete is poured for the slab; or    -   hollow in that the geometric configuration of material is such        that at least 25% of a horizontal cross-section of the void        system is open, not any type of solid material.

For the purposes of determining if a majority of a type of formwork isnot manually removed in order to determine if a type of formwork meetsthe definition of a voidform, the formwork is a voidform if it is notremoved from a majority (e.g. 51%) of the slab area of the formworkwherein formwork is removed completely between the slab and thesubgrade. In a hybrid foundation, consisting of more than one type offormwork, determination if a type of formwork meets the definition of avoidform is made separately for each type of formwork (e.g. areas wheretemporary lumber shoring has been removed are not relevant to thedetermination of whether traditional carton voidforms are voidforms).

Examples of voidform systems include degradable corrugated papervoidforms, often with vertical partitions creating a cellularconfiguration with sets of these cells surrounded by corrugated paper,all produced with varying degrees of moisture protection as follows orin various combinations. “Uncoated” describes corrugated paper voidformsthat have no protective material used to either coat or impregnate theforms, and therefore are not protected from water, soil, moisture,insects, or micro-organisms. “Wax Coated” describes a process that isused to coat only the exterior liner surface of corrugated papervoidforms. This process temporarily helps maintain structural integrity,should the corrugated paper voidforms come in contact with moisturebefore or during the foundation construction. “Wax Impregnated”describes the result of a process that saturates individual papers usedto manufacture corrugated paper voidforms with wax. Fully waximpregnated describes the result of a manufacturing process where allpaper components (e.g. liners and mediums) are wax impregnated.

Compressible and/or hollow metal voidforms, are lightweight metalcomponents that are fabricated to configure a voidspace system. Anexample is an expanded sheet metal material that is repetitively slitand pulled to expand into diamond shape open areas leaving connectingstrands of metal having an average open space of 75 to 80 percent. Thematerial in one example can be formed into a configuration of corrugatedvertical segments. Metal voidforms can be compressible and can behollow.

Degradable molded paper voidforms, made from 100% recovered paper pulp,recycled paper, and/or recovered Kraft paper slurries that are shapedinto a product. Compressible and/or hollow plastic voidforms orcompressible and/or hollow hybrid plastic and corrugated papervoidforms, with plastic elements that can be made from up to 100%recycled plastic, often polypropylene. Hybrid plastic and corrugatedpaper voidforms can consist of vertical plastic partitions creating acellular configuration with corrugated paper material that surroundssets of vertical plastic partitions.

Compressible and/or hollow Styofoam voidforms are molded into anupside-down “U”-shaped or a box-shaped voidform. Compressible Styrofoamvoidforms are solid but have sufficient compressibility. They mayinclude compressible conglomerations of smaller particles, such asuncompacted soil, loose sand, uncompacted cinders, and/or styrofoampeanuts, having sufficient compressibility overall in theirconglomerated configuration.

Examples of systems that provide formwork over a subgrade but are notvoidform systems are:

-   -   Slab on metal deck, wherein the metal deck forms the bottom of a        slab but it also structurally spans between steel beams that are        foundation elements of a composite slab over a conventional        crawlspace;    -   Slab over temporary wooden formwork, wherein the majority of the        wooden formwork is manually removed after the slab is installed;        and    -   Slab on grade wherein the slab is poured over a vapor barrier        sheet or a vapor retarder sheet that covers the ground, wherein        the sheet does not sufficiently degrade or compress and is not        sufficiently hollow.

For purposes of this disclosure a foundation element is a component of afoundation for a building, not including a slab of a slab-on-voidformfoundation, not including a voidform system and not including a framingsystem. A foundation element is a structural member or connectionbetween structural members, wherein the members are commonly identifiedor addressed somewhere on foundation drawings or specifications,structural drawings or specifications, or architectural drawings orspecifications. Examples of materials that typically comprise afoundation element are concrete, steel, aluminum, masonry, timber, fiberreinforced polymer or a combination of these materials. A foundationelement is not a microscopic element, not a theoreticallyinfinitesimally small element, and not a portion of a larger elementthat is manufactured at one time. A foundation element is necessary forthe structural functions of a foundation after construction of thebuilding is complete, wherein a portion or portions of a foundationelement may not be necessary but some portion of a foundation element isnecessary. Furthermore, foundation elements are configured to be capableof being installed before the slab is installed. Examples of foundationelements are drilled concrete piers, augured cast in place piles, steelpiles, helical piles, micropiles, timber piles, pier caps, pile caps,gradebeams or walls that are poured directly on the ground, gradebeamsor walls that are poured over a system that is similar to a voidformsystem for a slab, steel columns and steel beams. Where the primary slaband other concrete elements are integrally poured together at the sametime, such as drop panels around drilled concrete piers or thickenedslab areas for slab recesses or internal stiffening beams, the otherconcrete elements that are integrally poured together with the primaryslab at the same time are parts of the slab and are therefore notfoundation elements.

For purposes of this disclosure, a subgrade within the perimeter of aslab-on-voidform foundation is material over which a voidform system isplaced in the construction of a slab-on-voidform foundation, whereinsaid material is not a part of a foundation element. Examples ofsubgrade material are clay, sand, silt, rocks, water, naturallyoccurring organic material, and combinations of these materials.Subgrade material also includes any manufactured materials, other thanfoundation elements, that are present when a voidform system is placedover the subgrade, with some examples being polyethylene vapor barriersheeting, polyethylene vapor retarder sheeting, injected lime slurry,injected proprietary chemical slurries, unreinforced concreteslabs-on-grade such as those commonly called “mudslabs”, and sometimesdebris like in a landfill or existing construction to be abandoned suchas an existing reinforced slab-on-grade.

For purposes of this disclosure, a hanger assembly is a system thatprovides support to an under-slab utility at one point along the lengthof the utility system, and the hanger assembly is supported by a framingsystem. A hanger assembly does not include any components of theunder-slab utility itself. Common examples of conventional hangerassembly components are adjustable clevis hangers, threaded rods, nutsand washers. Another example of hanger assembly components could be apipe clamp that is bolted to a framing system, wherein the pipe could bebelow or above the framing system, noting that it is still a hangerassembly even if the pipe is located above the framing system such thatthe hanger assembly is not in tension like a conventional threaded rodthat supports a pipe below a framing system. Examples of common hangerassembly materials are galvanized steel, stainless steel, aluminum andfiber reinforced polymer.

For purposes of this disclosure, an under-slab utility is a systemunderneath a slab of a slab-on-voidform foundation, wherein the systemtransmits something to the occupants from outside of the building, fromthe occupants to outside of the building, between areas of the building,or between buildings. Examples of such utility systems are sanitarysewer, domestic water, fire protection, natural gas, outside air forventilation, heated air, cooled air, electricity, and data systems. Itis common for an under-slab utility to include a pipe or conductorsystem that contains what is being transmitted. While under-slabutilities can often span a limited distance between supports, theytypically require supports be located much closer together than thedistance apart that foundation elements are typically located in aslab-on-voidform foundation.

For purposes of this disclosure a framing system is a system thatconsists of at least one beam and at least one beam-to-foundationelement connection, wherein a beam-to-foundation element connectionprovides support to a beam. In this disclosure a “beam” is also referredto as a “utility support member,” and the terms beam and utility supportmember are intended to be used interchangeably. A framing system doesnot include any foundation elements, does not include a slab of aslab-on-voidform foundation, and does not include voidforms. Abeam-to-foundation element connection can consist of one or more membersand connectors so as to elevate the supports for the beams in theframing system to a specified elevation relative to the foundationelements. A framing system can include at least one beam-to-beamconnection, wherein a beam provides support for another beam. Examplesof the components of connections can include plates, angles, brackets,post bases, posts, bolts, washers and nuts. Altogether, a framing systemis configured to be capable of being supported by at least onefoundation element and capable of supporting the weight of an under-slabutility system at the floorplan location or locations where said supportis required for the under-slab utility system. Examples of supportpatterns for beams of a framing system can be beams simply spanningbetween two supports, beams supported by three or more supports, beamscantilevered off of a fixed support, and beams cantilevered off of abeam that is supported at two points. Examples of point loading on beamsfor a framing system can be simple or complex, depending on the specificneeds of the project, where a beam could only have one point load at ahanger assembly, could have multiple hangers assemblies on one beam,could be supporting another beam that supports hanger assemblies, couldbe supporting multiple such beams, and could be supporting one or moresuch beams while also supporting one or more hanger assemblies.

In one embodiment a method of isolating under-slab utilities from asubgrade under a slab of a slab-on-voidform foundation is employedwhereby a framing system is attached to one or more foundation elementsof said slab-on-voidform foundation wherein said framing system isconfigured to not be in contact with subgrade. A hanger assembly is usedto suspend a segment of a utility line wherein said hanger assembly isconfigured to be supported by said framing system and also configured tobe above said slab, partially or completely embedded in said slab, orbelow said slab, wherein said hanger assembly is configured so that saidhanger assembly and said utility are to not be in contact with saidsubgrade. Voidforms are placed over said subgrade and a slab is pouredover the voidforms.

In another embodiment a method of isolating under-slab utilities fromsoil under a slab of a slab-on-voidform foundation is employed whereby atemporary support apparatus is used. In an embodiment a temporarysupport apparatus is comprised of a stake, a rod and an adjustablesupport nut is secured in a subgrade. Other configurations of atemporary support apparatus could include a frame which is driven intothe subgrade and extends above a slab, could include a structure that isplaced on a subgrade and extends sufficiently high enough to providetemporary utility support, could include a variation with a two partstructure in which a lower part that bears on a subgrade is notremovable after slab reinforcement is installed but an upper part isremovable after utilities are suspended by permanent components of aslab-on-voidform foundation, could be comprised of materials such asdimensioned lumber, masonry, light gage steel studs, strut channels, andplastic members. In an embodiment, when a vapor barrier is used andtemporary members are removed after a vapor barrier is installed, thevapor barrier could be patched where the removal creates a penetrationin the vapor barrier. A framing system comprised of utility supportmembers is attached to the temporary support apparatus, wherein saidframing system is configured to not be in contact with the subgrade. Ahanger assembly is used to suspend a segment of a utility line, whereinthe hanger assembly is configured to be supported by the framing systemand also configured to be partially or completely embedded in the slabwhile not being in contact with said subgrade. Voidforms are then placedover the subgrade, slab reinforcement is installed over reinforcementsupports, the utility support framing system is tied to the slabreinforcement, and the rod is then removed from said temporary supportapparatus. A slab is then poured over the voidforms.

In another aspect, the invention could include a permanent supportapparatus that supports under-slab utilities under a slab of aslab-on-voidform foundation wherein the permanent support apparatus issupported by a subgrade but all components of said permanent supportapparatus that are below said slab are not in contact with any portionof an under-slab utility or a hanger assembly for an under-slab utility,thereby transferring all forces associated with volumetric soil changesto said slab or foundation elements which will have a significantlygreater ability to resist volumetric soil changes than a typicalunder-slab utility. This could include a stake, a rod and a support nutsimilar to an embodiment of a temporary support apparatus as describedabove but wherein the rod is not removed because the slab is capable ofresisting the uplift forces associated with expansive soil pushing up onthe stakes. In another embodiment, a permanent support apparatus couldbe comprised of dimensioned lumber, masonry, cold-formed metal framingstuds, strut channels and plastic members.

In an embodiment of an apparatus of the invention, first and secondmembers are employed. Each of the first and second members has: a lengthin the range of 2 to 24 inches; a first side surface having a width inthe range of 1 to 2 inches; a second side surface having a width in therange of 1 to 2 inches; a third side surface having a width in the rangeof 1 to 2 inches. In the apparatus a third member is connected to thefirst and second members. The third member spans the distance betweenthe first and second members without intermediate support. The thirdmember has: a length in the range of 12 to 30 feet; a first side surfacehaving a width in the range of 1 to 2 inches; a second side surfacehaving a width in the range of 1 to 2 inches; a third side surfacehaving a width in the range of 1 to 2 inches. The first, second, andthird members may be composed of steel, stainless steel aluminum, orfiber reinforced polyurethane.

In one embodiment a utility support framing system of the inventioncomprises strut channel framing, such as produced by Unistrut or Eaton.In an embodiment the concrete foundation, and the utility supportframing system is above a vapor barrier over Masonite over void formsover soil. Also, in an embodiment, a layer of void forms immediatelyunder Masonite, which is a part of the voidforms, comprises a main slabvoid layer. Below the main slab void layer, a lower void space can becomprised of additional layers of void forms. In a preferred embodimentthe void forms comprising the main slab void layer, an additional layerof void forms below and soil define an interstitial space. In anotherembodiment, an interstitial space is defined by Masonite, the void formscomprising the main slab void layer, and an additional layer of voidforms below. In an embodiment, the utility support framing system isused to fasten a fiberglass threaded rod from the strut channel into theinterior space. In an embodiment the fiberglass threaded rod is used tosuspend a fiberglass saddle that holds utility piping.

In practicing an embodiment of the inventive method a utility supportframing system is supported vertically only by foundation elements(including but not limited to piers, caissons, piles, mini-piles, gradebeams, and footings) which are designed to resist volumetric soilchanges (including but not limited to expansive soil, frost heave,collapsible soil, etc. . . . ) in the active zone by sufficientisolation from soil and/or penetration below the active zone.

Further, the utility support system is installed before the utilities,void forms and reinforced concrete slab are installed and the concreteis cured, allowing the utilities to be installed and inspected beforethe slab is poured.

It also includes a feature that allows the flow line elevations of theutility piping to be adjusted by adjusting (including, but not limitedto, turning the supporting nuts in) the hanger assembly after theframing system deflects, before it is inspected.

Further, there are no components concealing or hindering any utilitypiping from visual inspection, flow line elevation measurement, andadjustment if inspection identifies any construction defects before autility is inspected.

It is also located in elevation so that it is above the soil supportingthe void forms, thereby creating a void to isolate the utilities fromsoil movement so that the framing does not need to be removed after theslab is poured.

Additionally, it does not include a soil retaining component in theframing or hanger assembly, which allows void forms to be placed oneither side of the piping (including but not limited to typical 4″diameter piping at sanitary sewer lines) so that the main layer of slabvoid forms immediately under the concrete slab can have a gap or bridgethemselves over a gap or be bridged over a gap with degradable materialsuch as Masonite.

The utility support framing system can be located in elevation above thevoidforms so that the framing generally does not interrupt the voidforms.

Further, the utility support framing system can be encased in theconcrete slab (including but not limited to locating the framing betweenthe upper and lower reinforcing bar mats that are common in such slabs,allowing for the framing level itself and the associated deflection ofthe framing to occur without interrupting the reinforcing bars if theslab is designed to be sufficiently thick, with the flexuralrequirements for reinforcing bars being reduced if the slab is made anythicker than it would otherwise be) to mitigate concerns with corrosionof the framing and also allow rebar to be installed without interruption(including but not limited to locating the framing in the middle portionof structurally suspended slabs which are less stressed in flexure thanthe upper and lower zones of the slab thickness and can thereforestructurally accommodate interruption by the framing as well asutilizing narrow portions of the slab in plan view at discrete points ofsupport such as piers or piles whereby this limits the impact of thisframing on the punching shear capacity of the slab).

It prevents any need for soil to contact hanger assemblies, therebyreducing corrosion potential. It further encases the utility supportframing system in the concrete slab itself, so that it has the samelevel of corrosion protection as the concrete reinforcing barsthemselves. And, because these are encased in concrete, even if it doescorrode, it will not fall down and cause damage (directly by falling, orindirectly by becoming a shin where a void was intended) to the utilitypiping as occurs with Indirect Bear Systems.

It can also be installed with hanger assembly materials that are morecorrosion resistant (including but not limited to fiberglass, stainlesssteel, aluminum and galvanized steel)

It also allows design professionals to design a soil retention systemusing any of the methods available to engineers in the prior art(including but not limited to vertical cuts in cohesive soil with anacceptable factor of safety, sloped grades in cohesion less soil basedon the angle of internal friction, retaining structures such as concretewalls, sheet piles, or other systems), and can be used where verticalcuts in soil and/or backfill adjacent to void forms that may overtimeallow a slope stability failure of the soil to occur if it is far enoughaway (including but not limited to a certain multiple of the verticalgrade change such as 1.5 or 2 times the height of the soil beingretained) so that the design professional does not anticipate any soilfalling under the utility piping.

The utility support framing system does not bear (directly orindirectly) on any soil within the active zone because the systeminstead bears on structural elements that are bearing on soil below theactive zone and/or are designed to sufficiently resist the verticalforces associated with volumetric changes in the active zone by virtueof their penetration below the active zone.

Also, the invention allows soil retainage to be designed by qualifieddesign professionals for each specific application, using methods in theprior art (including but not limited to temporary vertical cuts incohesive soil where there is an acceptable factor of safety, sloping thegrade to an acceptable stable slope such as the angle of repose forcohesionless soils, and installing permanent concrete retaining walls).In an embodiment, the invention allows this because the main voidformsbear on lower voidforms with a maximum gap that the main layer ofvoidforms can reliably bridge with degradable material such as cartonvoid forms. For example, 4″ diameter PVC sanitary sewer lines can beinstalled with lower void forms on each side, slotting the void forms toaccommodate any saddles and flanges.

Additionally, the invention does not allow soil in a subgrade to contactany of the hanger assemblies. Furthermore, generally corrosion resistantmaterials such as fiberglass, aluminum, stainless steel and galvanizedsteel are available with invention to resist any ambient sub-slabmoisture for an even longer useful life expectancy.

The invention allows full inspection of piping as required by buildingcodes.

Further, because the invention allows independent soil retainingsystems, a flexible expansion joint can be installed to successfullytransition between suspended and soil-supported sections of utilitypiping. Flexible expansion joints utilize rotating and telescopingjoints available in the prior art.

Also, the invention avoids the need for maintenance associated withdamage caused by expansive soil or any other type of volumetric soilchanges, which can happen in the prior art as noted above. It alsoallows independently designed soil retaining systems, where designprofessionals can create sufficiently large void spaces along the sidesof the utility piping that can be more-easily accessed horizontallythrough openings in exterior grade beams by removing exterior backfill(rather than cutting holes vertically into the slabs and hand-diggingfrom the opening to pipe location which can often be over 20 feet fromthe nearest potential location for a temporary slab opening).

An embodiment of the invention comprises of a protective utilitycounterweight with a larger pipe and encasing the soil-supported utilityline in concrete with a felt separation, with sufficient length anddiameter of the protective utility counterweight to provide structuralstability to cantilever one end through a vertical slot in a foundationelement with the vertical slot having sufficient height to accommodateat least the potential vertical movement up or down from initialposition, in which a flexible expansion joint is initially installed ata slope that is the minimum slope required by the applicable plumbingcode plus the slope required to allow the soil-supported end to rise atleast the estimated potential vertical movement, in which the soil isretained by soil retaining boards that are penetrated by the over-sizedpipe of the protective utility counterweight, and there is sufficientlength and weight of concrete to provide a minimum factor of safety of1.5 to resist the overturning associated with the full weight of theflexible expansion joint (applicable when the joint is disconnected fromthe slab-hung end for installation or replacement), and in which thediameter of the concrete in-fill is sufficient to reduce the bearingstress on the utility to a level that will not damage the utility pipeas it pushes up and down on the concrete which in turn pushes up anddown on the soil-retention boards. This embodiment utilizing aprotective utility counterweight and a flexible expansion joint, withone or more mountable pipe clamps connecting a suspended utility pipe toa foundation element, fully isolates the suspended portions of utilitiesfrom expansive soil changes or any other type of volumetric soilchanges. Soil is retained from encroaching under the flexible expansionjoint with commercially available materials that can horizontally spanthe vertically slotted hole to accommodate any height of hole required,wherein these boards can slide up and down along the side of thefoundation elements. Further, providing a concrete collar around theutility pipe helps to avoid breaking the utility pipe as it engages thesoil retention boards. Also, in an embodiment a counter-weight andretention protection collar that is similar in shape to the utility pipeis provided. This reduces the difference in potential vertical movement,relative to the subgrade adjacent to the utility and outside of abuilding, while also providing a transitional drainage region over thepipe where the pipe itself beyond the concrete encasement reduces thepotential vertical movement also and provides a path for positivedrainage. Additionally, protecting the utility with felt that allowsreplacement of the piping in the future may be incorporated.Furthermore, making the length of the concrete encasement approximately5 or 6 feet allows specification of the system to fall within theindustry standard scope of one design professional (a mechanicalengineer) rather than two (a mechanical engineer and a civil engineer).

Additionally, practicing one embodiment of the invention, includesinstalling all of the foundation elements and a suspended structuralsupport for a mountable pipe clamp, with an oversized opening for afixed elevation building condition utility pipe and an oversized openingfor a protective utility counterweight that allows sufficient verticalclearance above and below the protective utility counterweight toaccommodate the potential vertical movement. It next involves installingunder-slab utility piping under all building areas, and installing oneor more mountable pipe clamps on each side of a suspended structuralsupport so that a utility pipe in a building cantilevers away from asuspended structural support while installing under-slab piping,installing this piping and clamps (with sealant around any pipingpenetrating an exterior grade beam being a preferred example) beforepouring a slab of a slab-on-voidform foundation or after installing afloor structure of a crawlspace foundation. The method then requiresexcavating outside of the foundation element where a protective utilitycounterweight will be installed, overexcavating away from the foundationelement sufficiently so that the protective utility counterweight can beslid into place through a hole in a slidable retainer board. It thenrequires installing a slidable retainer board, with a hole sized toreceive a protective utility counterweight, onto the side of afoundation element over the oversized hole made to receive a protectiveutility counterweight, surveying the elevation of the cantilevered pipeand then bolting the top of the slidable retainer board at the elevationwhich will set the hole in the board at the elevation which accommodatesthe specified initial vertical offset from the cantilevered pipe of thebuilding. The next step requires compacting subgrade materials under theelevation of the proposed bottom of the protective utilitycounterweight, with bentonite as an example of a subgrade materialagainst the slidable retaining wall, extending 6″ for example past theedges of the slidable retainer board, but stopping a few inches belowbelow the proposed bottom elevation of the protective utilitycounterweight. Then the protective utility counterweight is lowered intothe excavation adjacent to the foundation element, using manpower, aforklift and/or a frame with a winch, and while it is suspended by thelowering mechanism, slide the protective utility counterweight throughthe hole in the slidable retainer board and then install shims totemporarily maintain the correct elevation of the protective utilitycounterweight relative to the building condition pipe elevation. Locateone set of shims so that they are at the end furthest away from theslidable retainer board and another set at the end inside the oversizedhole in a foundation element which the protective utility counterweightcantilevers through. Next, concrete or flowable concrete fill isinstalled as a leveling bed of subgrade material under the proposedprotective utility counterweight between the slidable retainer board andthe set of shims furthest from the slidable retainer board, pouring upto a point below the middle of the protective utility counterweight asneeded to stabilize the elevation for the current soil conditions.Install bentonite as an example so that the concrete leveling bed doesnot contact the slidable retainer board itself. Temporary shims are thenremove the temporary shims. Soil supported plumbing from the site isthen attached to a utility pipe that extends through the protectiveutility counterweight, cantilever past the end of the protective utilitycounterweight so as to receive a flexible expansion joint. Subgradematerial is then compacted under, around and on top of the protectiveutility counterweight to achieve the finished subgrade elevation desiredoutside of the building. Be careful to not change the elevation of theprotective utility counterweight during compaction operations, resettingthe pipe if it shifts during compaction operations. A flexible expansionjoint is then lowered into the gap between the cantilevered buildingcondition pipe and the cantilevered site condition pipe, connecting theflexible expansion joint to each pipe end. Finally an access hatch ordoor that may be required by building code or desired to allowinspection and maintenance of the flexible expansion joint is installed.

In an another embodiment, stakes and rods are employed so that thestakes can be hammered into the subgrade for a slab-on-voidformfoundation before the voidforms are installed, then the rods can beinstalled so as to provide temporary support for utility framing,bearing on an adjustable nut that can be set at an elevation compatiblewith the voidforms height and slab thickness. In an embodiment, a headedbolt could be installed into the stakes to protect the rod duringhammering and keep soil/debris from getting into the threaded hole, or asmooth hole, at the top of the stake. The headed bolt can then beremoved and the main support rods are then installed, with support nutand utility support framing bearing on the support nut. Then thevoidforms are installed and reinforcing bars for the slab of theslab-on-void foundation. Then, before concrete is poured, the utilitysupport framing can be tied with wire to the reinforcing bars (which aresupported by the voidforms at that point in the method), and, as thismakes the rods no longer necessary, the rods can be removed by hand ormechanically by a wrench, or by installing a double nut or a lock nut ora lock nut and a conventional nut on the rods, above the utility supportframing members, and turning the double nut assemblage or lock nut so asto unthread the threaded rod from the support nut, and if the hole inthe stake is threaded then remove the stake below as well. An open-endedsocket wrench can be used for this purpose. And an open-ended box wrenchcan be used to stabilize the support nut below while turning the doublenut assemblage. The small holes in the voidforms can then be patchedwith plastic sheeting (typically used as a vapor barrier). This solvesthe above problem by providing support that is temporarily on the groundbefore voidforms are installed but then removed after voidforms are inplace before concrete is poured.

Another embodiment of the invention includes a retaining structure thatdoes not extend below the bottom of the trench so that it is capable ofsliding horizontally if expansive soil swells, sliding until the soilhas swollen as much as it needs to relieve internal soil pressurebuild-up. The maximum vertical movement estimated by geotechnicalengineers is commonly reported when expansive soils are encountered. Anembodiment of the invention includes an approach which provides a gapbetween the wall and the utilities (and utility supports), so that itwill not damage the utilities if the wall slides.

The embodiment allows design and installation without knowing what theexpansive soil pressures are because it is designed based on themagnitude of the potential vertical movement, which is commonly reporteddata, allowing a horizontal gap of that same magnitude which is themaximum possible horizontal movement from expansive soil because volumechange is three-dimensional.

Because the system is capable of sliding without damaging utilities,this invention can be approved by building officials as an “alternativemethod of construction”, avoiding the need to resist the overturning andsliding with a factor of safety of 1.5 due to expansive soil swelling,which would otherwise not be permitted by building codes.

The embodiment also takes advantage of the cohesion of the earth commonin soil under slab-on-voidform foundations by digging a trench in thesoil so that the cohesive soils maintain the shape of the trench longenough for concrete to be poured in the trench. This avoids the costs ofconstructing formwork for the retaining structure and the costs ofremoving such formwork.

No reinforcement is necessary with this invention, because the wall issimply a “gravity wall”. “Engineered Gravity Wall” retaining structuresin the prior art are embedded below the soil on both sides.“Unengineered Gravity Wall” retaining structures that are in the priorart which do not extend below the lower elevation are common for minor“unengineered” retaining walls such as landscaping “railroad tie”timbers or simple border stones laid on the ground with landscapingbehind the stones. This invention is constructed similar to an“unengineered gravity wall” used in landscaping but is engineered to becapable of resisting the active soil pressures required by the buildingcode and it forgoes the extension of the wall under the grade of thetrench so as to be capable of sliding. It is also different from eitherstyle of gravity wall in the prior art because it is earth formed onboth side and then excavated on one side to expose the entire height ofthe wall. It is furthermore different in that there is a gap between thewall and utilities set based on the expansive soil potential verticalmovement so as to avoid damaging utilities.

Furthermore, the embodiment allows decking such as plywood or metal deckor plastic formboards to be installed on top of the retaining structureson each side of the plumbing trench, or conventional retainingstructures, or ledger supports attached to the side of foundationelements, so as to support carton or other voidforms without the need tocut voidforms around intricate areas of complex plumbing distributionsystems. The decking is not attached to the supports so that differentsystems do not have undesirable forces from expansive soil movement(e.g. a foundation element will not have upward pressures as expansivesoil causes a retaining structure to shift upward as the expansive soilswells).

Lower-cost, low strength, flowable concrete fill and/or “lean concrete”without coarse aggregate can also be used with this invention so as tomake it easy for “joists” (e.g. horizontal strut channels under deckingwhere the longitudinal axis of utility trenches change and/or deckingneeds additional support) to be installed in seats that are formed orcut into the retaining structures so that the joists are not attached tosupports but the joists can be attached to the decking. This allows theplumbing elevation to occur immediately below the decking or joists forthe decking so as to maximize the suitability for this application tomore scenarios on a project as utilities slope in elevation. Inpracticing the invention a level ground surface is crated by cutting andfilling operations. Wall trenches are excavated on each side of proposedutility locations, providing a horizontal clear dimension between theproposed utilities and the proposed walls equal to the potentialvertical movement estimated by the geotechnical engineer of record withthe depth and width installed to be capable of resisting bothoverturning and sliding by a factor of safety of 1.5 against the activesoil loads required by the building code if the soil between the walltrenches were to be removed. Concrete is poured in the wall trenches.After curing the concrete, soil is excavated between the walls over thefull depth of the walls. Stakes and rods are installed on each side ofthe concrete walls. The stakes have a sharpened edge at the bottom, areembedded in the soil and they have a smooth or threaded hole in the top.Threaded rods are installed in each stake, and support nuts areinstalled on each rod. Horizontal strut channel is installed over thesupport nuts. Hanging pipe supports are installed to suspend utilitiesover a voidspace equal or greater than the potential vertical movement.Decking is installed over the plumbing trench between the concrete wallsand additional framing supports added where necessary support of deckingis not provided by walls, with the decking being supported by theconcrete walls without attaching decking to the walls. Support may alsobe provided by installing ledger supports onto the side of foundationelements, without attaching decking to the ledger supports. Voidformsare installed over the walls and decking, with no voidforms necessaryunder the decking or supports described. Rebar is installed for the slabof the slab-on-voidform foundation, using bar support spacers. Strutchannels are tied at each hanger assembly to the rebar in the slab ofthe slab-on-voidform foundation. The rods are removed from the stakes bypreventing rotation of the supporting nuts (e.g. with an open-endedwrench) and rotating the threaded rod by hand, or by installing two nutsat the top and wrenching them together so as to effectively create atemporary bolt-head that can be used to remove the rod more quickly witha power drill and a socket bit. Finally, the concrete foundation ispoured. As an example, in an embodiment the web of a strut channel couldface downward, leaving an opening at the top of the strut channel thatallows concrete to flow into the strut channel as it is mechanicallyvibrated during concrete placement. This allows the strut channel tofunction as additional reinforcement in the slab.

The invention can also incorporate installing a novel mountable pipeclam as shown in the figures, allowing a method and system for resistingaxial and transverse forces placed on a pipe that cantilevers from afixed foundation element to support and connect to a flexible expansionjoint that will shift during volumetric soil changes. Installing a pairof mountable pipe clamps as shown in the figures provides a method ofresisting moments in such a condition. The pair of mountable pipe clampscan be mounted at any desired elevation and any desired horizontallocation perpendicular to the face of the wall from which a pipecantilevers, for a pipe within an opening of any size or geometry, andcan be removed and remounted using other locations of the inventivedevice for bolt holes that do not interfere with the original boltlocations, avoiding the need for coring an existing bolt. And, as apair, if the holes in the mountable pipe clamps on each side of a wallare aligned, bolts can be installed that extend through the wallentirely.

Furthermore, installing a mountable pipe clamp on one face of afoundation element will lock a pipe into a position and make it possiblefor sealant to be added all around the pipe between the pipe and theopening on the other side of the foundation element, before installingthe second mountable pipe clamp on that face.

Furthermore, this mountable pipe clamp can allow inspection of anysealant added behind the pipe clamp and a second mountable pipe clampcan be removed to remove old sealant and reapply new ones and thenreinstall the mountable pipe clamp. If bolts are used with nuts, thenuts could be removed in such an application so that the bolts and nutscan even be reused after sealant has been replaced.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross sectional view of an embodiment of the invention.

FIG. 2 shows a side view of an embodiment of the invention.

FIG. 3 shows a partial side view of an embodiment of the invention.

FIG. 4 shows a cross sectional view of an embodiment of the invention.

FIG. 5 shows a cross sectional view of the embodiment of the invention.

FIG. 6 shows a cross sectional view of an embodiment of the invention.

FIG. 7 shows a plan view of an embodiment of the invention.

FIG. 8 shows a plan view of an embodiment of the invention.

FIG. 9 shows a plan view of an embodiment of the invention.

FIG. 10 shows a plan view of an embodiment of the invention.

FIG. 11 shows a side view of an embodiment of the invention.

FIG. 12 shows a cross sectional view of an embodiment of the invention.

FIG. 13 shows a side view of an embodiment of the invention.

FIG. 14 shows a cross sectional view of an embodiment of the invention.

FIG. 15 shows a cross sectional view of an embodiment of the invention.

FIG. 16 shows a cross sectional view of an embodiment of the invention.

FIG. 17 shows a cross sectional view of an embodiment of the invention.

FIG. 18 shows a cross sectional view of an embodiment of the invention.

FIG. 19 shows a cross sectional view of an embodiment of the invention.

FIG. 20 shows a cross sectional view of an embodiment of the invention.

FIG. 21 shows an elevation view of an embodiment of the invention.

FIG. 22 shows a cross sectional view of an embodiment of the invention.

FIG. 23 shows a cross sectional view of an embodiment of the invention.

FIG. 24 shows a cross sectional view of an embodiment of the invention.

FIG. 25 shows a cross sectional view of an embodiment of the invention.

FIG. 26 shows a cross sectional view of an embodiment of the invention.

FIG. 27 shows a plan view of embodiments of the invention.

FIG. 28 shows a plan view of embodiments of the invention.

FIG. 29 describes methods of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cross sectional view of an embodiment of the inventionwherein a utility pipe [101] is hanging over a subgrade [102] from oneor more hanger assemblies [103]. A hanger assembly [103] is connected toand supported by one or more utility support members [104] of theinventive framing system.

In an embodiment, utility pipe [101] is comprised of polyvinyl chloride,cast iron, or galvanized steel. Furthermore, in an embodiment, utilitypipe [101] is a component of a sanitary sewer plumbing system, adomestic water supply system, a fire protection system, a natural gaspiping system, an electrical power supply system or a telecommunicationssystem.

Furthermore, in an embodiment, hanger assembly [103] is comprised ofgalvanized steel, stainless steel or plastic. Also, in an embodiment,hanger assembly [103] includes a partially or completely threaded rodwith a nut and washer configurable above a utility support member [104]wherein the threaded rod hangs from the utility support member [104] andcould include a clevis hanger that holds a utility pipe [101] with a nutunder a portion of a clevis hanger wherein the clevis hanger hangs fromthe threaded rod and the elevation of the clevis hanger can be adjustedby turning a nut above a utility support member [104].

In an embodiment, a utility support member [104] is comprised ofungalvanized steel, galvanized steel, stainless steel or plastic.Furthermore, in an embodiment, utility support member [104] could be astrut channel with 12 gage thickness and regularly spaced slotted holesin the web of the strut channel. Alternatively, in an embodiment,utility support member [104] could be a hollow, rectangular steel tube.Also alternatively, in an embodiment, utility support member [104] couldbe rebar such as might be used as slab reinforcement for a concreteslab. As an example, in an embodiment a washer, as part of a hangerassembly, above a utility support member [104] could be a strut channelsaddle washer if the utility support member [104] is a strut channel.

Also, in an embodiment, the difference in elevation between the bottomof a hanger assembly [103] and a subgrade [102] could be established toprotect a utility pipe [101] by being greater than or equal to thepotential vertical movement of the subgrade [102] due to volumetricchanges of the subgrade as estimated by a geotechnical engineer.

FIG. 2 shows a side view of an embodiment of the invention as shown inFIG. 1.

FIG. 3 shows a partial side view of an embodiment of the inventionwherein an inventive temporary support apparatus [301] includes aninventive stake [302], a threaded rod [303] and an adjustable supportnut [304]. In practicing an embodiment of a method of the invention, theinventive stake [302] is driven into a subgrade [102]. A threaded rod[303] is inserted into a hole at the top of an inventive stake [302]wherein the inventive stake [302] provides support for the threaded rod[303]. An adjustable support nut [304] is connected to and supported bythe threaded rod [303].

In an embodiment, the inventive stake [302] has a sufficiently longlength such that it can be driven into a subgrade [102] to a sufficientdepth that provides a desired or greater level of rigidity for use inthe inventive temporary support apparatus [301]. Also, in an embodimentthe inventive stake [302] has a sufficiently short length so that, afterthe inventive stake [302] is driven into a subgrade [102] to asufficient depth that provides a desired or greater level of rigidityfor use in the inventive temporary support apparatus [301], theinventive stake [302] could be driven further if necessary so that thetop of the inventive stake [302] will not extend above the subgrade[102] more than the difference between a specified height of voidformsproposed under a slab of a slab-on-voidform foundation and the potentialvertical movement estimated by a geotechnical engineer for the subgrade[102].

In an embodiment of a method of the invention, a threaded rod [303] isinserted into the inventive stake [302] after the inventive stake [302]is driven into a subgrade. The elevation of an adjustable support nut[304] is adjusted to a desired elevation by turning an adjustablesupport nut [304] after the threaded rod [303] is inserted into theinventive stake [302] after the inventive stake was previously driveninto a subgrade [102], thus adjusting for a specific embedment depth ofthe inventive stake [302] into the subgrade [102].

In an embodiment, the inventive stake [302] is comprised of steel.Further, in an embodiment, the inventive stake [302] is 18 inches long.In embodiments, the inventive stake [302] has a round cross sectionalshape or a rectangular cross sectional shape. As an example, theinventive stake [302] can have a round cross sectional shape with anouter diameter that is ¾ inches with a round hole that is 2½ inches deepand ½ inches in diameter. In another example, the inventive stake [302]could have an unthreaded hole with smooth sides. Further, in anembodiment, the inventive stake [302] could have a threaded hole. Also,in an embodiment the inventive stake [302] could have a “v” shapedbottom with two sloped surfaces that form a linear edge along thebottom. In other embodiments, the inventive stake [302] could have asingle-sloped bottom, a flat bottom, a conical bottom that forms apointed tip, or a hemispherical shaped bottom.

Further, in embodiments, the threaded rod [303] is completely threadedor partially threaded. Furthermore, the threaded rod [303] could have aconsistent diameter inclusive of any threads over the length of thethreaded rod [303] or it could have varying diameters, inclusive of anythreads, allowing an adjustable support nut [304] to slide withoutturning where the diameter of the threaded rod is greater than thediameter of portions of a threaded rod [303]. Furthermore, in anembodiment the threaded rod [303] is comprised of ungalvanized steel orgalvanized steel. Further, the adjustable support nut [304] may becomprised of ungalvanized steel or galvanized steel.

FIG. 4 shows a cross sectional view of an embodiment of the inventionwherein a utility pipe [101] is hanging over a subgrade [102] from oneor more hanger assemblies [103]. The hanger assembly [103] is connectedto and supported by one or more utility support members [104] of theinventive framing system. In the embodiment, one or more utility supportmembers [104] of the inventive framing system are supported, partiallyor completely, by one or more inventive temporary support apparatuses[301]. In the embodiment, the subgrade [102] is be benched so as tocreate a plumbing trench with steps in the sides of the plumbing trencharranged geometrically in a manner that is compatible with placement ofrectangular voidforms on the subgrade [102] and also prevents anunacceptable amount of subgrade [102] material from entering the spaceunder a utility pipe [101] or a hanger assembly [103] after a concreteslab of a slab-on-void foundation is poured.

FIG. 5 shows a cross sectional view of the embodiment of the inventionshown in FIG. 4 after voidforms [501] are installed, after slabreinforcement [502] is installed, wherein slab reinforcement [502] issupported by one or more reinforcement supports [503] that are supportedby voidforms [501], after one or more utility support members [104] ofthe inventive framing system are tied to the slab reinforcement [502]with tie wire (or other similar fastener such as, but not limited to,zip ties, bailing wire, reinforcement ties, string or the like) [504] soas to stabilize the utility support member [104] in preparation forremoving portions of any inventive temporary support apparatuses [301]before a concrete slab of a slab-on-voidform foundation is poured aswell as in preparation for any static water pressure testing of one ormore utility pipes [101] before a concrete slab of a slab-on-voidformfoundation is poured.

In an embodiment, the voidforms [501] are comprised of a wax coatedcardboard, plastic, or a hybrid of plastic materials and degradablematerials, if sufficient separation is provided between voidforms [501]and any utility pipes [101] as well as between voidforms [501] and anyhanger assemblies [103]. Further, in an embodiment, a protectivevoidform sheathing [505], as a component of the voidforms, could beinstalled at the top of the voidforms [501] over any spaces betweenvoidform [501] components installed to accommodate any hanger assemblies[103], and utility pipes [101] and any inventive temporary supportapparatuses [301]. Also in an embodiment, the degradable protectivevoidform sheathing [505] could be 9/32 inches thick oriented strandboard with sufficient structural span rating to be capable, for therequired spans, of supporting the loads associated with pouring aconcrete slab of a slab-on-voidform foundation or 9/32 inches thickplywood with sufficient structural span rating to be capable, for therequired spans, of supporting the loads associated with pouring aconcrete slab of a slab-on-voidform foundation.

Furthermore, by way of example, vapor barrier [506], as part of theslab, could be installed over the voidforms [501] or could be capable ofadhering to the bottom of a concrete slab so that it will remain in theinstalled position after any degradable voidforms [501] degrade. As anexample, sealant [507], as part of a vapor barrier [506] which is partof a slab, could be installed around any holes [508] where components ofthe hanger assembly [103] where the hanger assembly [103] penetrates avapor barrier [506], with the sealant [507] penetrating into any threadsof a component of a hanger assembly [103].

As an example, the tie wire [504] material could be steel wire commonlyused to tie reinforcement for reinforced concrete construction. Also asan example, slab reinforcement [502] could be #5 reinforcing bars at 12inches on center each way at the top of a slab and #5 reinforcing barsat 12 inches on center each way at the bottom of a slab. As an example,reinforcement supports [503] could be individual wire reinforcementsupports at 3 feet on center each way under each mat of slabreinforcement.

As an example, double nut [509] could be installed at the top of anytemporary support apparatuses [301] to effectively create a bolt headthat allows convenient removal of portions of the temporary supportapparatus before a concrete slab of a slab-on-voidform foundation ispoured. Also, in an embodiment, a lock nut could be installed at the topof any temporary support apparatuses [301] to effectively create a bolthead that allows convenient removal of portions of the temporary supportapparatus before a concrete slab of a slab-on-voidform foundation ispoured.

In an embodiment, before a concrete slab of a slab-on-voidformfoundation is poured, any threaded rods [303] and adjustable supportnuts [304] that are part of the inventive temporary support apparatus[301] could be removed by preventing rotation of the adjustable supportnuts [304] at a constant elevation while turning the threaded rods [303]until the threaded rods [303] completely rise up above a utility supportmember [104], removing the threaded rods [303] and the adjustablesupport nuts [304] so that the threaded rods [303] do not transfer anyloads to the foundation from volumetric soil changes, leaving theinventive stake [302] in the subgrade [102].

FIG. 6 shows a cross sectional view of an embodiment of the inventionshown in FIG. 5 after removal of components as described for FIG. 5,leaving any inventive stakes [302] in the subgrade [102], afterinstalling vapor barrier patches [601], as part of the vapor barrier[506] which is a part of the slab [603] of a slab-on-voidformfoundation, over any vapor barrier holes [602], and after pouring aconcrete slab [603] of a slab-on-voidform foundation.

FIG. 7 shows a plan view of an embodiment of the invention wherein autility support member [104] of the inventive framing system isconnected to and supported by another utility support member [104] ofthe inventive framing system with one or more connectors [701] securedby one or more bolts [702]. In an embodiment, the connectors [701] couldbe a pair of matching horizontal plates above and below the utilitysupport member [104] which are compatible with the utility supportmember [104]. Also, in an embodiment, the connection could consist ofwelding utility support members [104] together in lieu of using a bolt.Additionally, in an embodiment, a hanger assembly [103] could besupported by a connector [701].

FIG. 8 shows a plan view of an embodiment of the invention wherein autility support member [104] of the inventive framing system isconnected with a connector [701] and bolts [702] to utility supportmembers [104] of the inventive framing system so that the two membersact compositely with greater strength and stiffness than one member. Inan embodiment, a pair of strut channels that are parallel could beconnected with a regularly spaced connector [701] that is a platecompatible with strut channel framing above and below the pair of strutchannels, allowing a flatter cross sectional geometry than combining thetwo strut channels with one on top of the other, as the flatter crosssectional geometry is more compatible with the invention to allow theutility support members [104] to be located between the upper and lowermats of reinforcement. In an embodiment, more than two strut channelsacting as utility support members [104] could be connected [701] in asimilar manner to maintain a relatively flat cross-sectional geometry soas to not require a thicker slab of a slab-on-voidform foundation.

FIG. 9 shows a plan view of an embodiment of the invention whereinutility support members [104] connected with connectors [701] and bolts[702] to act compositely as shown in FIG. 8 wherein a hanger assembly[103] supported by the connector [701]. As an example, a pair ofparallel utility support members acting compositely are spaced to allowfor a hanger assembly [103] to be hanging from the center of gravity ofthe composite combination of utility support members, which avoidstwisting the utility support members [104].

FIG. 10 shows a plan view of an embodiment of the invention wherein autility support member [104] could be connected to and supported by acomposite of utility support members [104] which are connected as shownin FIG. 8 with a connector [701] and bolts [702].

FIG. 11 shows a side view of an embodiment of the invention wherein oneor more utility support members [104] are connected to and supported byone or more foundation elements [1101] with one or more post-installedelevation support connectors [1102] so that the one or more utilitysupport members [104] cantilever and support a hanger assembly [103] aswell as a perpendicular utility support member [104] so that the utilitypipe [101] is not in contact with the subgrade [102]. As an example, apost-installed elevation support connector [1102] could include strutchannel post bases, angles and bolts that are compatible with strutchannel framing, and post-installed anchors into one or more foundationelements [1101]. Additionally, in an embodiment a foundation elementcould be a drilled and reinforced concrete pier.

FIG. 12 shows a cross sectional view of an embodiment of the inventionsimilar to that shown in FIG. 1 but with two composite utility supportmembers [104] of the inventive framing system attached by connectors[701].

FIG. 13 shows a side view of an embodiment of the invention wherein oneor more wet-set elevation support connectors [1301] are set into thefresh concrete when one or more foundation elements [1101] are poured,and one or more utility support members [104] extends to anothersupport, with a utility support member [104] being connected to andsupported by a utility support member [104] which is supported by afoundation element [1101]. The one or more utility support members [104]are connected to and supported by one or more elevation supportconnectors [1301] so that the elevation of one or more utility supportmembers [104] can be adjusted to a desired elevation. As an example, autility support member supported by a foundation element [1101] on oneend could be supported on another end by another foundation element[1101] as shown in FIG. 13. As an example, a utility support membersupported by a foundation element [1101] on one end could be supportedon another end by another utility support member [104].

FIG. 14 shows a cross sectional view of an embodiment of the inventionwherein one or more utility support members [104] of the inventiveframing system are shown to span structurally between two foundationelements [1101] without any need for intermediate support, supportingthe loads of one or more hanger assemblies [103], the loads of one ormore utility pipes [101], and the loads of other utility support members[104] that are connected to and supported by the one or more utilitysupport members [104] that span between the two foundation elements. Asan example, a pair of parallel utility support members [104] could bemade into a composite structural element with periodically spacedconnectors [701] and bolts [702] as shown in FIG. 8 with connectors[701] on both the top and bottom of the utility support member [104] asshown in FIG. 14, with a nut attached to a bolt [702] that is used tomake the pair act compositely. In an embodiment the conditions at eachfoundation element [1101] as shown in FIG. 14 are similar to theconditions shown in FIG. 13. As an example, in an embodiment theconditions at the hanger assembly [103] as shown in FIG. 14 are similarto the conditions shown in FIG. 6 but tie wire [504] could be installedto connect a utility support member [104] to reinforcement [502] so asto stabilize the hanger assembly [103] so that the utility pipe [101]could be static water tested without the additional weight of the watercausing deflection of the utility support members [104] spanning longdistances between foundation elements [1101] which would cause a changein the flow line elevations of the utility pipes [101] that may beunacceptable in that the changes in flow line elevations may impair thefunctionality of the utility pipe [101]. In another example, one or moreutility support members [104] can be at a height determined by verticalsupport member [1301] so that the elevation of the utility supportmembers [104] is between the upper and lower mats of reinforcement [502]where the utility support members [104] can be cast permanently into theslab [603] of a slab-on-voidform foundation without impairing theability of the reinforcement [502] and the slab [603] to functionstructurally as the slab [603] structurally spans between foundationelements [1101] over a subgrade [102] without being in contact with asubgrade [102].

FIG. 15 shows a cross sectional view of an embodiment of the inventionwherein one or more inventive mobile retaining walls [1501] areeconomically earth-formed by excavating and filling the excavation withconcrete. In an embodiment there is a mobile retaining wall [1501] oneach side of a proposed plumbing trench. As an example, the mobileretaining wall [1501] has a cross sectional geometry that is at least aswide as it is tall, which prevents the mobile retaining wall [1501] fromtipping over when functioning as a retaining wall that has lateralexpansive soil pressures. Furthermore, in an embodiment the mobileretaining wall [1501] is comprised of flowable concrete fill with atleast 110 pounds per cubic foot density and no course aggregate,concrete with at least 140 pounds per cubic foot density and no courseaggregate or concrete that is unreinforced.

FIG. 16 shows a cross sectional view of an embodiment of the inventionwherein a utility pipe [101] is hanging over a subgrade [102] from oneor more hanger assemblies [103], similar to that shown in FIG. 4. Ahanger assembly [103] is connected to and supported by the one or moreutility support members [104] of the inventive framing system, similarto that shown in FIG. 4. In an embodiment, one or more utility supportmembers [104] of the inventive framing system is supported, partially orcompletely, by one or more inventive temporary support apparatuses[301], similar to that shown in FIG. 4. As an example, a subgrade [102]could be excavated adjacent to one or more inventive mobile retainingwalls [1501] so as to create a plumbing trench arranged geometrically ina manner that is compatible with placement of rectangular voidforms[501] on a subgrade [102] and also prevent subgrade [102] material fromentering the space under a utility pipe [101] or a hanger assembly [103]after a concrete slab of a slab-on-void foundation is poured. In anembodiment, one or more inventive stakes [302] which are part of one ormore inventive temporary support apparatus [301] could be driven intoone or more mobile retaining walls [1501] instead of a subgrade [102].Also, in an embodiment, utility support members [104] could structurallyspan between foundation elements [1101] as shown in FIG. 14, over aplumbing trench that is created by excavating adjacent to one or moremobile retaining walls [1501] rather than benching the sides of aplumbing trench.

FIG. 17 shows a cross sectional view of an embodiment of the inventionsimilar to that shown in FIG. 5 but with a plumbing trench that iscreated by excavating adjacent to one or more mobile retaining walls[1501], rather than benching the sides. In an embodiment, decking [1701]could be installed over mobile retaining walls [1501] so as to create asupport system for voidforms [501] above decking [1701], which reducesor eliminates a need to cut voidforms around complex utility pipe [101]configurations below decking [1701] and thereby reduces the number ofdays between rain events necessary to allow for any degradable voidforminstallation above decking [1701] if decking [1701] material issufficiently rigid. Decking [1701] has gaps to allow for penetrationssuch as hanger assemblies [103]. In an embodiment, voidforms [501] couldbe degradable carton voidforms and decking [1701] material could bedegradable plywood. In another embodiment, voidforms [501] could beplastic voidforms and decking [1701] material could be plastic. In yetanother embodiment, voidforms [501] could be a hybrid of plastic andcarton material and decking [1701] could be galvanized corrugated metaldeck. As another example, voidforms [501] could be degradable cartonvoidforms and decking [1701] material could be nondegradable.

FIG. 18 shows a cross sectional view of an embodiment of the inventionsimilar to that shown in FIG. 6 but with a plumbing trench that iscreated by excavating adjacent to one or more mobile retaining walls[1501], rather than benching the sides without impairing the utilitypipe [101] or hanger assembly [103].

FIG. 19 shows a cross sectional view of an embodiment of the inventionas shown in FIG. 18 wherein voidforms [501] and decking [1701] could bedegradable and after any degradable material has degraded and areduction in subgrade [102] volume has occurred.

FIG. 20 shows a cross sectional view of an embodiment of the inventionsimilar to that shown in FIG. 18 wherein voidforms [501] and decking[1701] are degradable after the after any degradable material hasdegraded and an increase in subgrade [102] volume has occurred withoutimpairing the utility pipe [101] or hanger assembly [103]. In anembodiment, the mobile retaining walls [1501] are installed adjacent toplumbing trenches, mobile retaining walls [1501] are allowed to slidelaterally if lateral forces from volumetric soil change exceed thesliding resistance of the mobile retaining wall as a gravity wallsystem. In an embodiment, the horizontal distance of separation betweena utility pipe [101] and a mobile retaining wall [1501] could be greaterthan or equal to the potential vertical movement estimated by ageotechnical engineer so as to protect the utility pipe [101] from theeffects of volumetric changes in soil.

FIG. 21 shows an elevation view of an embodiment of the inventionwherein an inventive mountable pipe clamp [2101] suitable for supportinga utility pipe [101] and simultaneously clamping onto utility pipe [101]to prevent vertical and horizontal movement of utility pipe [101] whenthe inventive mountable pipe clamp [2101] is mounted onto a structurewith a utility opening that is larger than the utility pipe [101] toallow construction tolerance and code-required felt so that the utilitypipe [101] can be removed and replaced. The inventive clamp [2101] issuitable for preventing rotation of a utility pipe [101] about atransverse axis of a utility pipe [101] when an inventive mountable pipeclamp [2101] is installed on two sides of a structure so as to create amoment arm of resistance against overturning. As an example, twomounting components [2102] together could comprise an inventivemountable pipe clamp [2101] when bolted together with two clamping boltand nut assemblies [2103]. In an embodiment, mounting components [2102]could consist of half of a standard pipe clamp [2104] that is theappropriate geometry to cradle a utility pipe [101] and a mounting arm[2105].

In an embodiment, the inventive mountable pipe clamp [2101] is comprisedof stainless steel, galvanized steel, or plastic. Also, in anembodiment, the mounting arm [2105] could be a strut channel withregularly spaced slotted holes in the web of a strut channel allowingconvenient options for mounting onto a structure a sufficient distanceaway from the edge of a utility opening. As an example, a half of astandard pipe clamp [2104] could be welded to a mounting arm [2105] tocreate a mounting component [2102]. Also, as an example, a mounting arm[2105] and components that have a similar shape to half of a standardpipe clamp [2104] could be fabricated as one plastic component.

FIG. 22 shows a cross sectional view of an embodiment of the inventionwherein an inventive protective utility counterweight [2201] provides aprotective collar around a utility pipe [101] so as to prevent theutility pipe [101] from breaking under certain loads, is sufficientlyrigid to cantilever support of a utility pipe [101] through an openingin a foundation element [1101], is sufficiently long and heavy to resistoverturning when it cantilevers support of a utility pipe [101] throughan opening in a foundation element [1101], and allows removal andreplacement of a utility pipe [101]. In an embodiment, the inventiveprotective utility counterweight [2201] could consist of an outer pipe[2202] with a larger diameter than a utility pipe [101] wherein theouter pipe [2202] is infilled with counterweight material [2203] arounda protective sheathing [2204] that acts as a bond breaker between thecounterweight material [2203] and a utility pipe [101].

FIG. 23 shows a cross sectional view of an embodiment of the inventionwherein a vault capable of housing a transition of utility pipes [101]from a building where a utility pipe [101] is supported similar to theconditions shown on FIG. 18 transitioning to where the utility pipe[101] is supported by an inventive protective utility counterweight[2201] that is supported by a subgrade [102] and can rise or fall if asubgrade experiences volumetric changes.

In an embodiment, the vault is comprised of foundation elements [1101]and reinforced concrete as the vault top [2301]. In another embodiment,the vault consists of reinforced concrete grade beams with a vault top[2301] that is poured over temporary formwork which is removed from thevault by an access opening [2302] which can be used for periodicinspection and maintenance. As another example, the access opening[2302] could be a manhole. As another example, the access opening [2302]could be an access door. In another embodiment, one or more foundationelements [1101] forming the perimeter of the vault could be one or morereinforced concrete grade beams or walls. It also incorporates aslidable soil retainer [2303], which is a soil retainer capable ofretaining soil and sliding up or down along the face of a foundationelement [1101] if a subgrade [102] experiences volumetric changes. As anexample, the slidable soil retainer [2303] could be comprised ofplastic. In another an example, the slidable soil retainer [2303] couldhave horizontally oriented flutes to span horizontally across an openingin the foundation element [1101]. In another example, the slidable soilretainer [2303] is comprised of concrete.

FIG. 23 shows an embodiment of the invention after the building iscomplete and the installation of the site has occurred up to the pointin time that the inventive protective utility counterweight [2201] hasbeen installed. In FIG. 23 an embodiment of the invention is shownwherein the inventive mountable pipe clamp [2101] has been installed onboth sides of a foundation element [1101] so that a utility pipe [101]cantilevers into the vault. FIG. 23 shows an embodiment of the inventionwherein a slidable soil retainer [2303], with a counterweight hole[2304] in it capable of accommodating the diameter of an inventiveprotective utility counterweight [2201], is initially bolted [2035] to afoundation element [1101] of the vault so that the slidable soilretainer [2303] can be temporarily fixed at a proper initial elevationto receive a flexible expansion joint that will transition the utilitypipe [101] from the building to the site, with the slidable soilretainer [2303] being bolted [2305] to the foundation element [1101]before backfilling against the slidable soil retainer [23003]. FIG. 23shows an embodiment of the invention after a slidable soil retainer[2303] is bolted [2305] to a foundation element [1101]. Subgrade [102]material is backfilled up to an elevation which is necessary for theinventive protective utility counterweight [2201] to be at a properelevation to receive a flexible expansion joint and be located in avertically slotted opening [2306] in a foundation element [1101] withsufficient clearance above and below the portion of the inventiveprotective utility counterweight [2201] that cantilevers through thevertically slotted opening [2306].

As an example, backfill material [2307], as part of a subgrade [102],against the slidable soil retainer [2303] could be expansive materialthat is capable of expanding when exposed to moisture so that it sealsoff gaps that may allow moisture to enter the vault and be capable ofexpanding with a subgrade [102] that is capable of experiencingvolumetric changes. As another example, backfill material [2307] againstthe slidable soil retainer could be bentonite extending 6 inches pastthe edges of the slidable soil retainer [2303] and extending 8 inchesaway from the exterior face of a foundation element [1101]. Also, in anembodiment, an inventive protective utility counterweight could besuspended by chains from a forklift and lowered to the correctelevation, slid through the counterweight hole [2304] of the slidablesoil retainer [2303], and then shims [2308] could be installed under theends of one or more inventive protective utility counterweights [2201]so that a levelling bed [2309], as part of a subgrade [102], can bepoured under the bottom of the inventive protective utilitycounterweight [2201]. In another example, levelling bed [2309] could becomprised of concrete, flowable concrete fill, or gravel.

FIG. 24 shows a cross sectional view of an embodiment of the inventionwherein a vault is capable of housing a transition of utility pipes[101] from a building where the utility pipe [101] is supported as shownon FIG. 18 to the utility pipe [101] being supported by an inventiveprotective utility counterweight [2201] that is supported by a subgrade[102] and can rise or fall if a subgrade experiences volumetric changes.As an example, in an embodiment a flexible expansion joint [2401] allowsfor rotation at each end of the flexible expansion joint [2401] as wellas telescoping capability in and out axially along the longitudinal axisof the flexible expansion joint [2401] so that the horizontal distancebetween the ends of the initial installation of the flexible expansionjoint [2401] could be constant while the vertical distance, thedifference in elevation, between the ends of the initial installation ofa flexible expansion joint [2401] could change by increasing anddecreasing in dimension within the limits of functionality for theflexible expansion joint [2401] such as the maximum vertical offset froma horizontal position for a particular flexible expansion joint. In anembodiment, the flexible expansion joint [2401] could be installed withthe vertical distance between the ends of the flexible expansion joint[2401] equal to the sum of the minimum required vertical fall to complywith applicable building code regulations and half of the maximumvertical offset from a horizontal position for a particular flexibleexpansion joint, allowing the site condition to rise half of the reservevertical offset capacity and to fall half of the reserve vertical offsetcapacity. In an embodiment, the flexible expansion joint [2401] could beinstalled to maximize the reserve upward vertical offset capacity byinstalling the elevation of an inventive protective utilitycounterweight [2201] at the steepest possible slope that the flexibleexpansion joint can provide, giving sufficient clearance above theinventive protective utility counterweight [2201] in the verticalslotted opening [2306]. As an example, in an embodiment a flexibleexpansion joint [2401] could be installed to maximize the reservedownward vertical offset capacity by installing the elevation of aninventive protective utility counterweight at the most shallow slopeallowed by applicable building code regulation, giving sufficientclearance under the inventive protective utility counterweight [2201] inthe vertical slotted opening [2306].

In an embodiment, the vault is comprised of foundation elements [1101]and a reinforced concrete slab as the vault top [2301]. In anotherembodiment, the vault is comprised of reinforced concrete grade beamswith a vault top [2301] that is poured over temporary formwork which isremoved from the vault by an access opening [2302] which can be used forperiodic inspection and maintenance. In another embodiment, the accessopening [2302] could be a manhole. In another embodiment, the accessopening [2302] could be an access door. In another embodiment, one ormore foundation elements [1101] forming the perimeter of a vault couldbe one or more reinforced concrete grade beams or walls. Also, slidablesoil retainer [2303] is a soil retainer capable of retaining soil andsliding up or down along the face of a foundation element [1101] if asubgrade [102] experiences volumetric changes.

Also, FIG. 24 shows an embodiment of the invention after the building iscomplete and a flexible expansion joint [2401] has been installed. FIG.24 shows an embodiment of the invention wherein an inventive mountablepipe clamp [2101] has been installed on both sides of a foundationelement [1101] so that a utility pipe [101] cantilevers into the vault.FIG. 24 also shows an embodiment of the invention wherein a slidablesoil retainer [2303], with a counterweight hole [2304] in it is capableof accommodating the diameter of an inventive protective utilitycounterweight [2201], after initially installing the inventiveprotective utility counterweight [2201] but before installing anysubgrade [102] material over the inventive protective utilitycounterweight, one or more temporary bolts [2035] that were used to holda slidable soil retainer [2303] in position are exposed by pulling backthe slidable soil retainer [2303] and then one or more temporary bolts[2035] are cut back to the face of a foundation element [1101] of thevault so that a slidable soil retainer [2303] can slide up or downwithout engaging any remaining portions of temporary bolts [2035] leftin an foundation element [1101]. In an embodiment, a flexible expansionjoint [2401] is connected to utility pipe at one end of the vault fromthe building and connected to utility pipe at the other end of the vaultfrom the site. In an embodiment, a flexible expansion joint [2401] couldtransition one or more utility pipes [101] from the building to thesite, with one or more slidable soil retainers [2303]. As an example,shims [2308] installed to facilitate installation of the inventiveprotective utility counterweight are removed and subgrade (102) materialis backfilled. FIG. 24 shows an embodiment of the invention whereinafter any bolts [2305] connecting a slidable soil retainer [2303] to afoundation element [1101] are removed, subgrade [102] material isbackfilled up to a final grade.

As an example, backfill material [2307], as part of a subgrade [102],against the slidable soil retainer [2303] could be expansive materialthat is capable of expanding when exposed to moisture so that it sealsoff gaps that may allow moisture to enter the vault and be capable ofexpanding with a subgrade [102] that is capable of experiencingvolumetric changes. As another example, backfill material [2307] againstthe slidable soil retainer could be bentonite extending 6 inches pastthe edges of a slidable soil retainer [2303] and extending 8 inches awayfrom the exterior face of a foundation element [1101].

FIG. 25 shows a cross sectional view of an embodiment of the inventionsimilar to FIG. 24, however FIG. 25 shows soil conditions after anincrease in soil volume has occurred and the volumetric soil change doesnot cause any impairment of the function of the utility pipe [101]. Asan example, FIG. 25 shows conditions in an embodiment if degradablevoidforms [501] are used with degradable deck [1701] and soil expansionoccurs over time after degradable voidforms [501] and degradable deck[1701] degrade and are no longer present.

FIG. 26 shows a cross sectional view of an embodiment of the inventionsimilar to FIG. 24, however FIG. 26 shows soil conditions after adecrease in soil volume has occurred and the volumetric soil change doesnot cause any impairment of the function of the utility pipe [101]. Asan example, FIG. 26 shows conditions in an embodiment if degradablevoidforms [501] are used with degradable deck [1701] and soil expansionoccurs over time after degradable voidforms [501] and degradable deck[1701] degrade and are no longer present.

FIG. 27 shows a plan view of an embodiment of the invention whereindegradable voidforms [501] could be used.

Further, FIG. 27 shows a plan view of an embodiment of the inventionwherein one or more utility pipes [101] are hanging from one or morehanger assemblies [103] and one or more hanger assemblies [103] areconnected to and supported by one or more utility support members [104]of the inventive framing system, as also shown in FIGS. 1, 2, 4-6, 11,12, 14, 16-20 and 23-26.

FIG. 27 further shows an embodiment wherein a utility pipes [101] form asystem [XXXX] that could be used for a sanitary sewer plumbing system ofa men's restroom with 2 water closets and 2 urinals, and a women'srestroom with 4 water closets, and each restroom having sinks, floordrains and clean outs as could be required by a locally adopted buildingcode or desired by an owner. As an example, utility pipes [101] could bearranged in a complex three-dimensional geometry. In another example,utility pipes [101] could create a partial slab penetration [2701]wherein one or more utility pipes [101] extend partially through a slab.As an example, in an embodiment the partial slab penetration [2701]could occur at a floor drain. As another example, a utility pipe [101]could create a full slab penetration [2702] wherein the utility pipe[101] extend completely through the slab. As another example, a fullslab penetration [2072] could occur at a water closet. As anotherexample, a full slab penetration [2072] could occur at a urinal. Also,in an embodiment, a full slab penetration [2072] could occur at a sink.As another example, in an embodiment, a full slab penetration [2072]could occur at a clean out. Also, a full slab penetration [2072] couldoccur at a vent pipe. For examples with utility types other thansanitary sewer plumbing, in an embodiment a full slab penetration [2072]could occur at a domestic water pipe. Also, as an example with utilitytypes other than sanitary sewer plumbing, in an embodiment a full slabpenetration [2072] could occur at an automatic fire sprinkler pipe.Also, as an example with utility types other than sanitary sewerplumbing, in an embodiment a full slab penetration [2072] could occur ata natural gas pipe. As another example with utility types other thansanitary sewer plumbing, in an embodiment a full slab penetration [2072]could occur at an electrical service pipe. Also, as an example withutility types other than sanitary sewer plumbing, a full slabpenetration [2072] could occur at a telecommunications cable. As anadditional example with utility types other than sanitary sewer pluming,a full slab penetration [2072] could occur at a duct for a heating,ventilation or air conditioning system. Also, as an example, in anembodiment one or more utility pipes [101] that extend partially orfully through the slab could be tied to one or more utility supportmembers [104] placed nearby the partial slab penetration [2701] or fullslab penetration [2702] so as to prevent a vertical utility pipe [101]from leaning over before the concrete for the slab [603] is poured.

As another example, hanger assemblies [103] could occur at every planview intersection of a utility pipe [101] and a utility support member[104]. Also, in an embodiment, hanger assemblies [103] could occurperiodically where utility pipes [101] are under and parallel with autility support member [104], at a spacing that is less than or equal tothe maximum permitted spacing of supports for a utility pipe [101]. Asan additional example, hanger assemblies [103] could occur periodicallywhere utility pipes [101] are under and parallel with a compositeassembly created by one or more utility support members [104] withconnectors [701], with the hanger assemblies occurring at a spacing thatis less than or equal to the maximum permitted spacing of supports for autility pipe [101] and the connectors [701] occurring periodically alongthe length of the composite assembly.

As another example, FIG. 27 shows 10 round foundation elements [1101]that could be 24 inch diameter drilled shaft reinforced concrete piers,with 8 of the piers on a consistent grid with each other, and these 8piers geometrically creating three distinct, not overlapping,rectangular bays each representing an area of a building floor plan witha pier at every corner of each bay, with the three bays shown in FIG. 27referred to herein as an exterior-most bay closest to the flexibleexpansion joint [2401] shown, an interior-most bay furthest from theflexible expansion joint [2401] shown and a center bay between theexterior-most bay and the interior-most bay.

The interior-most bay shown in FIG. 27 shows a plan view of anembodiment of the invention wherein one or more utility support members[104] as part of the inventive framing system are supported by one ormore inventive temporary support apparatuses [301] as shown in FIG. 4-6,allowing a high degree of flexibility in placing one or more inventivetemporary support apparatuses [301] so as to work around closely spacedutility pipes, especially where they could be relatively close inelevation to the bottom of the slab [603] of a slab-on-voidformfoundation, as a higher elevation of utility pipes [104] generally makesinstallation of the invention more economical and practical.

The center bay of FIG. 27, which is referenced herein to include an areanear the boundary of the center bay and the interior-most bay as well asan area near the boundary of the center bay and the exterior-most bay,shows a plan view of an embodiment of the invention wherein one or moreutility support members [104] as part of the inventive framing systemare supported by one or more other utility support members [104],wherein connectors [701] would be used as shown in FIGS. 7 and 10. Inthe embodiment the center bay of FIG. 27 shows a plan view of theinvention wherein one or more utility support members [104] as part ofthe inventive framing system are supported by one or more foundationelements [1101], as shown in FIGS. 11, 13 and 14. Utility supportmembers [104] could be supported in some locations by one or moreinventive temporary support apparatuses [301] and in other locations byone or more other utility support members [104] and in other locationsby foundation elements [1101]. Also, in an embodiment, embodiment shownin the center bay could be more economical than the approach shown inthe interior-most bay because the approach shown in the center bay hassignificantly fewer inventive temporary support apparatuses [301],considering that while the inventive temporary support apparatuses [301]can reduce the length of utility support member [104] material requiredthe inventive temporary support apparatuses [301] also create obstaclesto placing voidforms [501] which makes the voidforms more expensive tocoordinate before fabrication of the voidforms [501] or to customize thegeometry of the voidforms [501] in the field, so it can therefore bemore economical to minimize the use of inventive temporary supportapparatuses [301] when there is a single utility pipe [101] in arelatively large area.

As an example, in an embodiment at the area near the boundary betweenthe exterior-most bay and the center bay, FIG. 27 shows a plan view ofan embodiment of the invention wherein one or more utility supportmembers [104] are connected with one or more other parallel utilitysupport members [104] to create a composite assembly that canstructurally span between supports, as shown in FIGS. 8, 13 and 14,using connectors as shown in FIG. 8, so as to provide a greater strengthand stiffness than would be provided with a single utility supportmember [104] while maintaining a relatively flat cross sectionalgeometry so that the assembly of utility support members [104] can belocated between an upper layer and a lower layer of reinforcing bars[502] in a slab [603] of a slab-on-voidform system, which could assistin making the design of the slab [603] more economical as it could avoida need to make the slab [603] thicker to accommodate a taller crosssectional geometry of an assembly of utility support members [104].

As an example, in an embodiment the exterior-most bay of FIG. 27 shows aplan view of an embodiment of the invention wherein relatively deeperelevations of one or more utility pipes [101] could be accommodated byinstalling one or more inventive mobile retaining walls [1501] to retainsoil, as shown in FIGS. 15-20, where this approach could be moreeconomical than excavating and maintaining a wide and deep trench inwhich the subgrade [102] is benched as shown in FIGS. 4-6 and 14.

In an embodiment, a decking support member [2703] could be used as partof the decking [1701]. As examples, the decking support member [2703]could be a light gage steel strut channel. Also as an example, in anembodiment the decking support member [2703] could be supported at eachend by one or more inventive mobile retaining walls [1501] wherein anotched seat for a decking support member [2703] is created. As anadditional example, in an embodiment the decking support member [2703]could be supported at each end by one or more inventive mobile retainingwalls [1501] wherein a notched seat for a decking support member [2703]is created by grinding with a hand-held power grinder into an inventivemobile retaining wall [1501]. As an additional example, a deckingsupport member [2703] could provide support to decking [1701] but not bemechanically joined to decking [1701]. As another example, in anembodiment a decking support member [2703] could be mechanically joined,such as with screws, to decking [1701] where decking [1701] is notmechanically joined to both an inventive mobile retaining wall [1501]and a foundation element [1101], as the inventive mobile retaining wall[1501] is designed to rise and fall with volumetric soil changes whereasa foundation element [1101] is designed to resist forces associated withvolumetric soil changes.

As an example, FIG. 27 shows a plan view of an embodiment of theinvention wherein a vault as shown in FIGS. 23-26 houses a transitionsupports of utility pipes [101] from a building to a site by virtue of aflexible expansion joint [2401] that is secured in place to preventlateral movement in either plan view direction, prevent verticalmovement, and prevent rotation about a transverse axis of a utility pipe[101] by a pair of mountable pipe clamps [2101] that are capable ofresisting the lateral forces and movements induced by a flexibleexpansion joint [2401] during installation and during use of theinvention after construction if soil changes in volume, as a flexibleexpansion joint [2401] has internal gaskets that create some friction asa flexible expansion joint telescopes in and out axially and rotates ateach end. In an example, the transition of support conditions couldoccur under the slab [603] of a slab-on-voidform foundation.Furthermore, in an example, the transition of supports could occuroutside of the plan view of a slab [603] of a slab-on-voidformfoundation. As an example, the transition of support conditions couldoccur partially under the slab [603] of a slab-on-voidform foundationand partially outside of the plan view of a slab [603] of aslab-on-voidform foundation. As an additional example, FIG. 27 shows aplan view of an embodiment of the invention wherein a slidable soilretainer [2303] and an inventive protective utility counterweight [2201]provide sufficient support for the site condition end of a flexibleexpansion joint [2401], as shown in FIGS. 23-26.

FIG. 28 shows a plan view of an embodiment of the invention similar tothe exterior-most bay of FIG. 27 wherein voidforms [501] withnon-degradable components could be used for an entire utility pipe [101]system as inventive mobile retaining walls [1501] are installed toretain the subgrade [102] and support decking [1701] as shown in FIGS.17-20, which could require that the elevations of the utility pipes[101] be lower than possible at the interior-most bay of FIG. 27 wheredecking [1701] is not used, even where the utility pipe [101] is near apartial slab penetration [2701] or full slab penetration [2702] andotherwise the utility pipe [101] could be higher, allowing for moreflexibility in scheduling construction to avoid delays caused by raindamaging degradable voidforms [501] or risks that damp degradablevoidforms [501] could collapse when concrete for a slab [603] is pouredin geographic areas or periods of time where rain occurs morefrequently, even though the material cost of non-degradable voidforms[501] could be higher than the cost of degradable voidforms [501]. In anembodiment decking [1701] as shown in FIGS. 17 and 18 could benon-degradable material that provides a permanent support for voidforms[501] with non-degradable components above the decking [501], asdegradable decking [1701] could deteriorate over time and allow anyvoidforms [501] with non-degradable components above the decking [501]to fall into the plumbing trench and possibly create a mechanism thatcould transfer forces to utility piping from volumetric soil changewhich could damage and/or impair the function of a utility pipe [101].

As an example, FIG. 28 shows a plan view of an embodiment of theinvention wherein intermediate trench walls [2801] within the plumbingtrench could provide intermediate support for decking [1701] so as toreduce the length of the span that the decking [1701] would need toaccommodate otherwise. Additionally, as an example, intermediate trenchwalls [2801] could be one or more walls as tall as adjacent inventivemobile retaining walls [1501]. Also, in an embodiment, intermediatetrench walls [2801] could be a framing system of beams and columns astall as adjacent inventive mobile retaining walls [1501]. As anadditional example, intermediate trench walls [2801] could bedry-stacked unreinforced and ungrouted concrete masonry units. As anexample, in an embodiment intermediate trench walls [2801] could bedry-stacked unreinforced and ungrouted concrete masonry units with anominal height to width ratio of 2 to 1. As an example, intermediatetrench walls [2801] could be comprised of unreinforced ungroutedmasonry. Also, in an embodiment, intermediate trench walls [2801] iscomprised of unreinforced grouted masonry. Also, in an embodiment,intermediate trench walls [2801] material could be reinforced masonry.In an embodiment intermediate trench walls [2801] could be comprised ofstainless steel. Also, as an example, in an embodiment intermediatetrench walls [2801] could be a framing system of stainless steel strutchannel beams and columns. In another embodiment intermediate trenchwalls [2801] could be comprised of galvanized steel. Also, as anexample, in an embodiment intermediate trench walls [2801] could be aframing system of galvanized strut channel beams and columns. Also, asan example, intermediate trench walls [2801] could be comprised ofplastic. As an additional example, in an embodiment intermediate trenchwalls [2801] is comprised of degradable material such as wood ifdegradable voidforms [501] and degradable decking [1701] are used abovethe degradable intermediate trench walls [2801]. As an additionalexample, in an embodiment intermediate trench walls [2801] could besupported by a foundation that supports the intermediate trench walls[2801]. As an additional example, in an embodiment vertical elementssuch as columns that are part of one or more intermediate trench walls[2801] could be supported by a foundation that supports the intermediatetrench walls [2801]. As an additional example, in an embodiment one ormore intermediate trench walls [2801] could be modified geometrically tonot interfere with one or more inventive temporary support apparatuses[301] that could be located in plan view such that they would otherwiseinterfere.

FIG. 29 describes methods of the invention. At Step 2901 piers, piercaps and grade beams are installed and wet-set elevation supportconnectors are wet-set in concrete where desired. In Step 2902 utilityretaining walls are installed where it will be desired to retain soilwith a retaining structure adjacent to on each side of the proposedutility as required, such as allowing a proposed clear dimension fromsoil under and adjacent to the utility and hanger assemblies equal to orgreater than the potential vertical movement. In Step 2903, utilitytrenches are excavated, allowing a proposed clear dimension from soilunder and adjacent to the utility and hanger assemblies equal to orgreater than the potential vertical movement, benching along the lengthof the utility trenches as required where soil is not retained byretaining structures, extending. In Step 2904, temporary supportapparatuses are installed. In Step 2905, post-installed elevationsupport connectors are installed. In Step 2906, utility support membersare installed as part of the utility support framing system that iscapable of supporting hanger apparatuses where necessary to support anunder-slab utility. In Step 2907, hanger assemblies are installed sothat they are supported by the utility framing system. In Step 2908,under-slab utilities are installed so that the utilities are supportedby the hanger assemblies. In Step 2909, where under-slab utilitiespenetrate gradebeams at the perimeter of slab-on-voidform slab areas,install a mountable pipe clamp on each side of the gradebeam so as toconnect the utility at the penetration to the gradebeam and providesufficient anchorage so that the utility can cantilever past thegradebeam. In Step 2910, any additional decking supports required areinstalled where required to support proposed decking, including anyintermediate support walls, any intermediate support beams and anyledgers attached to foundation elements. In Step 2911, decking isinstalled over retaining walls and other decking supports such asintermediate support walls, intermediate support beams and ledgersattached to foundation elements. In Step 2912, voidforms are installed.In Step 2913, vapor barriers and components of vapor barrier systems areinstalled, including components around penetrations by hanger assembliesthrough the vapor barrier. In Step 2914, slab reinforcement is installedover reinforcement supports that bear on the vapor barrier. In Step2915, tie wire is installed to connect utility support members tostabilize them so that they will not move substantially after removal ofthe rods from temporary support apparatuses or during a concrete pour.In Step 2916, rods from temporary support apparatuses are removed. InStep 2917, the concrete of the slab is poured. In Step 2918, anexcavation is made to access the vertically slotted opening in afoundation element which will receive a protective utility counterweightand the slidable soil retainer which retains soil from entering thevertically slotted opening is bolted to the foundation elements at thetop of the slidable soil retainers. In Step 2919, backfill with subgradematerial, including bentonite against the slidable soil retainer isinstalled to raise the subgrade elevation to the bottom of the hole inthe slidable soil retainer. In Step 2920, the protective utilitycounterweight is installed in the correct position and placed on shimsat each end of the protective utility counterweight. In Step 2921,concrete is poured under the protective utility counterweight in betweenthe slidable soil retainer and the shims furthest from the foundationelement with the vertically slotted opening and the shims are removedfrom under the protective utility counterweight. In Step 2922, the boltsconnecting the slidable soil retainer to a foundation element are groundback so as to allow the slidable soil retainer to slide in the future ifexpansive soil causes the elevation of the slidable soil retainers torise or fall. In Step 2923 subgrade material is backfilled to raise thesubgrade elevation over the protective utility counterweight to thefinal grade elevations, including bentonite immediately against theslidable soil retainer. In Step 2924, the flexible expansion joint isinstalled. In Step 2925, the slab over the flexible expansion joint isformed with temporary shoring that is removed after the slab is poured,and the slab includes a means of access such as a manhole cover or door.

Numerous embodiments are described in this disclosure and are presentedfor illustrative purposes only. The described embodiments are notintended to be limiting in any sense. The invention is widely applicableto numerous embodiments, as is readily apparent from the disclosureherein. These embodiments are described in sufficient detail to enablethose skilled in the art to practice the invention, and it is to beunderstood that other embodiments may be utilized and that structuraland other changes may be made without departing from the scope of thepresent invention. Accordingly, those skilled in the art will recognizethat the present invention may be practiced with various modificationsand alterations. Although particular features of the present inventionmay be described with reference to one or more particular embodiments orfigures that form a part of the present disclosure, and in which areshown, by way of illustration, specific embodiments of the invention, itshould be understood that such features are not limited to usage in theone or more particular embodiments or figures with reference to whichthey are described. The present disclosure is thus neither a literaldescription of all embodiments of the invention nor a listing offeatures of the invention that must be present in all embodiments.

1. A method of isolating under-slab utilities from a subgrade under aslab of a slab-on-voidform foundation comprising: a. attaching a framingsystem to one or more foundation elements of said slab-on-voidformfoundation wherein said framing system is configured to not be incontact with the subgrade; b. using a hanger assembly to suspend asegment of said under-slab utilities prior to pouring concrete of theslab of the slab-on-voidform foundation wherein said hanger assembly isconfigured to be supported by said framing system and said hangerassembly is also configured to not be in contact with said subgrade; andc. wherein the framing system is comprised of one or more utilitysupport members.
 2. The method of claim 1 wherein the under-slabutilities are not in contact with said subgrade.
 3. The method of claim1 wherein the framing system is comprised of one or more utility supportmembers connected to and supported by one or more elevation supportconnectors that are connected to and/or supported by one or morefoundation elements.
 4. The method of claim 1 wherein at least one ofthe one or more utility support members is connected to and supported byone or more additional utility support members.
 5. The method of claim 1wherein the one or more of the utility support members structurally spanbetween two or more foundation elements without any need forintermediate support.
 6. The method of claim 1 wherein two or more ofthe utility support members are connected to form one or more compositeutility support members.
 7. The method of claim 1 wherein two or more ofthe utility support members are connected to form a composite utilitysupport member wherein the two or more of the utility support membersare connected side by side such that at any given transverse crosssection the top of the composite utility support member is at the sameelevation as the top of each component utility support member.
 8. Themethod of claim 1 wherein one or more of the one or more utility supportmembers is connected to slab reinforcement by a tie wire.
 9. The methodof claim 1 wherein said framing system is configured so that said one ormore utility support members are partially embedded in said slab. 10.The method of claim 1 wherein said framing system is configured so thatsaid one or more utility support members are completely embedded in saidslab.
 11. The method of claim 1 wherein said framing system isconfigured to be completely encased in concrete
 12. The method of claim1 wherein said framing system is configured so that said one or moreutility support members are above said slab.
 13. The method of claim 1wherein said framing system is configured so that said one or moreutility support members are below said slab.
 14. The method of claim 1wherein said framing system is configured so that said one or moreutility support members are below said slab and said hanger assemblyextends vertically into said slab.
 15. The method of claim 1 whereinsaid framing system is configured so that said one or more utilitysupport members are below slab reinforcement.
 16. The method of claim 1wherein said framing system is configured so that said one or moreutility support members are above slab reinforcement.
 17. The method ofclaim 1 wherein said framing system is configured so that said one ormore utility support members are between upper and lower mats of slabreinforcement.
 18. The method of claim 1 wherein said under-slab utilityis plumbing and said framing system is configured so that all of saidone or more utility support members, without any intermediate support,are between upper and lower mats of slab reinforcement after said hangerassembly and said plumbing is installed but before any plumbing isfilled with water.
 19. The method of claim 1 wherein two or more of theutility support members are connected with one or more connectors toform one or more composite utility support members wherein said hangerassembly is supported by one of said one or more connectors.
 20. Themethod of claim 1 wherein the smallest distance between the subgrade andthe hanger assembly is greater than or equal to the potential verticalmovement of the subgrade.
 21. The method of claim 1 wherein the smallestdistance between the subgrade and the under-slab utilities is greaterthan or equal to the potential vertical movement of the subgrade.
 22. Aframing system for suspending under-slab utilities under a slab ofslab-on-voidform foundation comprising: a. one or more elevation supportconnectors configured to be wet-set into or post-installed onto one ormore foundation elements of said slab-on-voidform foundation; b. saidelevation support connectors each comprising a strut channel having alength of 2-24 inches; c. one or more utility support members eachcomprising a strut channel having a length of 12-30 feet; d. each ofsaid elevation support connectors connected to one or more utilitysupport members; and e. said one or more utility support membersconfigured to attach to a hanger assembly.
 23. The system of claim 22wherein the elevation support connectors and the utility supportconnectors have regularly spaced slotted holes in the web of the strutchannel.
 24. The system of claim 22 wherein one or more connectionsbetween one or more elevation support connectors and one or more utilitysupport members comprises an angle that is bolted to an elevationsupport connector and bolted to a utility support member.
 25. The systemof claim 22 wherein one or more connections between one or moreelevation support connectors and one or more utility support memberscomprises an angle that is welded to an elevation support connector andwelded to a utility support member.
 26. The system of claim 22 whereinone or more elevation support connectors is welded to one or moreutility support members.
 27. The system of claim 22 wherein an end ofone or more utility support members is connected to an end of anotherutility support member by a bolted splice connector.
 28. The system ofclaim 22 wherein two or more parallel utility support members arealigned with the tops of the utility support members being at the sameelevation and the utility support members being connected to each otherso as to create a composite utility support member.
 29. The system ofclaim 22 wherein at least one of the one more utility support members isoriented with the web at the bottom.
 30. The system of claim 22 furthercomprising one or more tie wires configured to connect at least one ofthe one or more utility support members to slab reinforcement.